{"nodes": [{"id": "0", "name": "ship propulsion"}, {"id": "1", "name": "critical temperature"}, {"id": "2", "name": "current density"}, {"id": "3", "name": "charge density waves"}, {"id": "4", "name": "penetration depth"}, {"id": "5", "name": "chemical vapor deposition"}, {"id": "6", "name": "brillouin zone"}, {"id": "7", "name": "kinetic energy"}, {"id": "8", "name": "symmetry breaking"}, {"id": "9", "name": "condensed matter physics"}, {"id": "10", "name": "liquid nitrogen"}, {"id": "11", "name": "yttrium barium copper oxide"}, {"id": "12", "name": "scanning tunneling microscopy"}, {"id": "13", "name": "josephson junctions"}, {"id": "14", "name": "iron selenide"}, {"id": "15", "name": "magnetic flux"}, {"id": "16", "name": "coulomb repulsion"}, {"id": "17", "name": "molecular beam epitaxy"}, {"id": "18", "name": "fermi arcs"}, {"id": "19", "name": "electric field"}, {"id": "20", "name": "specific heat"}, {"id": "21", "name": "grain boundary"}, {"id": "22", "name": "unit cell"}, {"id": "23", "name": "order parameter"}, {"id": "24", "name": "magnetic resonance imaging"}, {"id": "25", "name": "short circuit"}, {"id": "26", "name": "carbon nanotubes"}, {"id": "27", "name": "ac losses"}, {"id": "28", "name": "bcs theory"}, {"id": "29", "name": "raman scattering"}, {"id": "30", "name": "fermi level"}, {"id": "31", "name": "condensed matter"}, {"id": "32", "name": "flywheel energy storage"}, {"id": "33", "name": "strontium titanate"}, {"id": "34", "name": "exchange interaction"}, {"id": "35", "name": "space group"}, {"id": "36", "name": "ion beam"}, {"id": "37", "name": "fermi surface"}, {"id": "38", "name": "metallic hydrogen"}, {"id": "39", "name": "finite element method"}, {"id": "40", "name": "magnetic field"}, {"id": "41", "name": "grain boundaries"}, {"id": "42", "name": "rare earth"}, {"id": "43", "name": "transmission electron microscopy"}, {"id": "44", "name": "phase diagram"}, {"id": "45", "name": "power transmission"}, {"id": "46", "name": "iron pnictides"}, {"id": "47", "name": "magnetic susceptibility"}, {"id": "48", "name": "neutron scattering"}, {"id": "49", "name": "strongly correlated"}, {"id": "50", "name": "coated conductor"}, {"id": "51", "name": "wind turbine"}, {"id": "52", "name": "hydrogen sulfide"}, {"id": "53", "name": "spectral weight"}, {"id": "54", "name": "coherence length"}, {"id": "55", "name": "optimally doped"}, {"id": "56", "name": "hubbard model"}, {"id": "57", "name": "density functional theory"}, {"id": "58", "name": "single crystal"}, {"id": "59", "name": "monte carlo"}, {"id": "60", "name": "mott insulator"}, {"id": "61", "name": "synchronous motor"}, {"id": "62", "name": "alternating current"}, {"id": "63", "name": "weak links"}, {"id": "64", "name": "liquid helium"}, {"id": "65", "name": "copper oxide"}, {"id": "66", "name": "sulfur hydride"}, {"id": "67", "name": "magnesium diboride"}, {"id": "68", "name": "nuclear magnetic resonance"}, {"id": "69", "name": "selenium hydrides"}, {"id": "70", "name": "meissner effect"}, {"id": "71", "name": "van hove"}, {"id": "72", "name": "electrical resistance"}, {"id": "73", "name": "room temperature"}, {"id": "74", "name": "transmission line"}, {"id": "75", "name": "stainless steel"}, {"id": "76", "name": "heat exchanger"}, {"id": "77", "name": "magnetic levitation"}, {"id": "78", "name": "charge carrier"}, {"id": "79", "name": "crystal structure"}, {"id": "80", "name": "quench propagation"}, {"id": "81", "name": "finite element"}, {"id": "82", "name": "insertion loss"}, {"id": "83", "name": "permanent magnet"}, {"id": "84", "name": "ground state"}, {"id": "85", "name": "perturbation theory"}, {"id": "86", "name": "induction motor"}, {"id": "87", "name": "charge transfer"}, {"id": "88", "name": "energy storage"}, {"id": "89", "name": "sol gel"}, {"id": "90", "name": "cooper pair"}, {"id": "91", "name": "heat capacity"}, {"id": "92", "name": "ab initio"}], "evolve_edges": [{"2000": [{"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2000}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 1.0, "year": 2000}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 1.0, "year": 2000}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2000}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 2.0, "year": 2000}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2000}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2000}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 1.0, "year": 2000}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2000}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2000}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 1.0, "year": 2000}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2000}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 4.0, "year": 2000}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2000}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 1.0, "year": 2000}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 1.0, "year": 2000}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 2.0, "year": 2000}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2000}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2000}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2000}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 1.0, "year": 2000}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2000}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2000}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 1.0, "year": 2000}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2000}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2000}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2000}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 1.0, "year": 2000}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2000}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 1.0, "year": 2000}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2000}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2000}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2000}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2000}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2000}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 1.0, "year": 2000}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 1.0, "year": 2000}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2000}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2000}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2000}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2000}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2000}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 1.0, "year": 2000}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2000}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2000}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 2.0, "year": 2000}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 1.0, "year": 2000}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 1.0, "year": 2000}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 1.0, "year": 2000}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 1.0, "year": 2000}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 2.0, "year": 2000}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 1.0, "year": 2000}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 1.0, "year": 2000}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 1.0, "year": 2000}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 1.0, "year": 2000}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2000}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 1.0, "year": 2000}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2000}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2000}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2000}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2000}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 2.0, "year": 2000}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2000}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2000}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 1.0, "year": 2000}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 1.0, "year": 2000}]}, {"2001": [{"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 2.0, "year": 2001}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2001}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2001}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2001}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 1.0, "year": 2001}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 3.0, "year": 2001}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2001}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 2.0, "year": 2001}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 2.0, "year": 2001}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2001}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2001}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 1.0, "year": 2001}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2001}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2001}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2001}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2001}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 1.0, "year": 2001}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2001}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 5.0, "year": 2001}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2001}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2001}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 1.0, "year": 2001}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 1.0, "year": 2001}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2001}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 2.0, "year": 2001}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2001}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 1.0, "year": 2001}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2001}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2001}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 1.0, "year": 2001}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2001}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2001}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2001}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2001}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 1.0, "year": 2001}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2001}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2001}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 1.0, "year": 2001}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2001}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2001}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 3.0, "year": 2001}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2001}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2001}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 1.0, "year": 2001}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 2.0, "year": 2001}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2001}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2001}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2001}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2001}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 1.0, "year": 2001}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2001}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 2.0, "year": 2001}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2001}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 1.0, "year": 2001}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2001}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2001}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2001}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2001}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 2.0, "year": 2001}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2001}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 1.0, "year": 2001}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 1.0, "year": 2001}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2001}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 1.0, "year": 2001}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2001}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2001}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2001}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2001}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2001}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2001}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 1.0, "year": 2001}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2001}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 2.0, "year": 2001}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2001}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2001}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2001}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 1.0, "year": 2001}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 1.0, "year": 2001}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2001}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2001}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 1.0, "year": 2001}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 2.0, "year": 2001}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2001}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 2.0, "year": 2001}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 1.0, "year": 2001}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 1.0, "year": 2001}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 2.0, "year": 2001}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 2.0, "year": 2001}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 2.0, "year": 2001}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 1.0, "year": 2001}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 3.0, "year": 2001}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2001}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2001}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2001}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 1.0, "year": 2001}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 1.0, "year": 2001}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 1.0, "year": 2001}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2001}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2001}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2001}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 1.0, "year": 2001}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2001}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2001}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 1.0, "year": 2001}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2001}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2001}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2001}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2001}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2001}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 1.0, "year": 2001}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2001}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2001}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 1.0, "year": 2001}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2001}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 2.0, "year": 2001}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2001}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2001}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2001}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 1.0, "year": 2001}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 1.0, "year": 2001}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 1.0, "year": 2001}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 1.0, "year": 2001}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2001}]}, {"2002": [{"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 3.0, "year": 2002}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2002}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2002}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2002}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 1.0, "year": 2002}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 1.0, "year": 2002}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 3.0, "year": 2002}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2002}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2002}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 2.0, "year": 2002}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 4.0, "year": 2002}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2002}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2002}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 2.0, "year": 2002}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 1.0, "year": 2002}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 1.0, "year": 2002}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2002}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2002}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2002}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2002}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2002}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 1.0, "year": 2002}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 1.0, "year": 2002}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2002}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 6.0, "year": 2002}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2002}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2002}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 1.0, "year": 2002}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 2.0, "year": 2002}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2002}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 2.0, "year": 2002}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2002}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2002}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2002}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2002}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2002}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2002}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 1.0, "year": 2002}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2002}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2002}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2002}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2002}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2002}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2002}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2002}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2002}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 1.0, "year": 2002}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2002}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 2.0, "year": 2002}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 1.0, "year": 2002}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2002}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2002}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2002}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2002}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2002}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2002}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 5.0, "year": 2002}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 1.0, "year": 2002}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 1.0, "year": 2002}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 1.0, "year": 2002}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2002}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 2.0, "year": 2002}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 2.0, "year": 2002}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2002}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2002}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2002}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2002}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2002}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2002}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2002}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 2.0, "year": 2002}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2002}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 2.0, "year": 2002}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2002}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 1.0, "year": 2002}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2002}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2002}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2002}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 1.0, "year": 2002}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 2.0, "year": 2002}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2002}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 1.0, "year": 2002}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 2.0, "year": 2002}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 1.0, "year": 2002}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2002}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2002}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2002}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 1.0, "year": 2002}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2002}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 1.0, "year": 2002}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2002}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2002}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2002}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2002}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2002}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2002}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2002}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2002}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2002}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2002}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 1.0, "year": 2002}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2002}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 2.0, "year": 2002}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2002}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 1.0, "year": 2002}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2002}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 1.0, "year": 2002}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2002}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2002}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 1.0, "year": 2002}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2002}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2002}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 2.0, "year": 2002}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 2.0, "year": 2002}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 1.0, "year": 2002}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2002}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 1.0, "year": 2002}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2002}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2002}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 4.0, "year": 2002}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 2.0, "year": 2002}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 1.0, "year": 2002}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 2.0, "year": 2002}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 2.0, "year": 2002}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2002}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 3.0, "year": 2002}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 5.0, "year": 2002}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 2.0, "year": 2002}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 4.0, "year": 2002}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2002}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2002}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2002}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 1.0, "year": 2002}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 1.0, "year": 2002}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2002}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 1.0, "year": 2002}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 1.0, "year": 2002}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2002}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2002}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2002}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2002}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 1.0, "year": 2002}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2002}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2002}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2002}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 1.0, "year": 2002}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2002}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2002}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2002}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2002}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2002}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2002}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2002}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2002}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2002}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2002}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2002}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 1.0, "year": 2002}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2002}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2002}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 1.0, "year": 2002}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2002}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2002}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 2.0, "year": 2002}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2002}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2002}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2002}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 1.0, "year": 2002}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2002}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2002}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2002}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 1.0, "year": 2002}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 1.0, "year": 2002}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 1.0, "year": 2002}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2002}]}, {"2003": [{"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 4.0, "year": 2003}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2003}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2003}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2003}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 1.0, "year": 2003}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 1.0, "year": 2003}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 4.0, "year": 2003}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2003}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2003}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 2.0, "year": 2003}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2003}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 1.0, "year": 2003}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 5.0, "year": 2003}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2003}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2003}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 3.0, "year": 2003}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 2.0, "year": 2003}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 2.0, "year": 2003}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 1.0, "year": 2003}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 2.0, "year": 2003}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2003}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2003}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2003}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2003}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2003}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2003}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2003}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 1.0, "year": 2003}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 1.0, "year": 2003}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 1.0, "year": 2003}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2003}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2003}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 6.0, "year": 2003}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2003}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2003}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 1.0, "year": 2003}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 2.0, "year": 2003}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2003}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 2.0, "year": 2003}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2003}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2003}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2003}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2003}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2003}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2003}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2003}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 1.0, "year": 2003}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 1.0, "year": 2003}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2003}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2003}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2003}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2003}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2003}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2003}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2003}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2003}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2003}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2003}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2003}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 2.0, "year": 2003}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 1.0, "year": 2003}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2003}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2003}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2003}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2003}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2003}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2003}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 6.0, "year": 2003}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 2.0, "year": 2003}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 2.0, "year": 2003}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 1.0, "year": 2003}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 1.0, "year": 2003}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 1.0, "year": 2003}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2003}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 2.0, "year": 2003}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 2.0, "year": 2003}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2003}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2003}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2003}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2003}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2003}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2003}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2003}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2003}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 2.0, "year": 2003}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2003}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 3.0, "year": 2003}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2003}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2003}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2003}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 1.0, "year": 2003}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2003}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2003}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2003}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 1.0, "year": 2003}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2003}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2003}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2003}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 1.0, "year": 2003}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2003}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2003}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 1.0, "year": 2003}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2003}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2003}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2003}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 1.0, "year": 2003}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 1.0, "year": 2003}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2003}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 1.0, "year": 2003}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2003}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 1.0, "year": 2003}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2003}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2003}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2003}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2003}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2003}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2003}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2003}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2003}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2003}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2003}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 1.0, "year": 2003}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2003}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2003}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2003}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2003}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 2.0, "year": 2003}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2003}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 1.0, "year": 2003}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 1.0, "year": 2003}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2003}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2003}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2003}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2003}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 1.0, "year": 2003}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2003}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2003}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 2.0, "year": 2003}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2003}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 1.0, "year": 2003}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2003}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 1.0, "year": 2003}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2003}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2003}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 1.0, "year": 2003}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 6.0, "year": 2003}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 3.0, "year": 2003}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 1.0, "year": 2003}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 1.0, "year": 2003}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 2.0, "year": 2003}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 2.0, "year": 2003}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2003}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 3.0, "year": 2003}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 5.0, "year": 2003}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 2.0, "year": 2003}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 4.0, "year": 2003}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2003}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2003}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2003}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 1.0, "year": 2003}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 1.0, "year": 2003}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 1.0, "year": 2003}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2003}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 1.0, "year": 2003}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 1.0, "year": 2003}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2003}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2003}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2003}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 2.0, "year": 2003}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 1.0, "year": 2003}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2003}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 1.0, "year": 2003}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2003}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2003}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 1.0, "year": 2003}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2003}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 1.0, "year": 2003}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2003}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2003}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2003}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2003}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2003}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 2.0, "year": 2003}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2003}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2003}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2003}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2003}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2003}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2003}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2003}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 1.0, "year": 2003}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2003}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2003}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 1.0, "year": 2003}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2003}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2003}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 2.0, "year": 2003}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2003}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2003}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2003}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 1.0, "year": 2003}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2003}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2003}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2003}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2003}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 1.0, "year": 2003}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 1.0, "year": 2003}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 1.0, "year": 2003}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2003}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 1.0, "year": 2003}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2003}]}, {"2004": [{"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 5.0, "year": 2004}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 1.0, "year": 2004}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2004}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2004}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2004}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2004}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 1.0, "year": 2004}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 4.0, "year": 2004}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2004}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2004}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 2.0, "year": 2004}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2004}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 1.0, "year": 2004}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 3.0, "year": 2004}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 7.0, "year": 2004}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2004}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2004}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 3.0, "year": 2004}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 2.0, "year": 2004}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 3.0, "year": 2004}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 2.0, "year": 2004}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 3.0, "year": 2004}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2004}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2004}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2004}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2004}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2004}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2004}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2004}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 1.0, "year": 2004}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 2.0, "year": 2004}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 1.0, "year": 2004}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2004}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2004}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2004}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2004}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 8.0, "year": 2004}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2004}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2004}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 5.0, "year": 2004}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 2.0, "year": 2004}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2004}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2004}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 2.0, "year": 2004}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2004}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2004}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2004}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2004}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2004}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2004}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2004}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2004}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 2.0, "year": 2004}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2004}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2004}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2004}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2004}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2004}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2004}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2004}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 1.0, "year": 2004}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 1.0, "year": 2004}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2004}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2004}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2004}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2004}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2004}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2004}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2004}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2004}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2004}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 2.0, "year": 2004}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 1.0, "year": 2004}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2004}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2004}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2004}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2004}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2004}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2004}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 7.0, "year": 2004}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2004}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 2.0, "year": 2004}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 2.0, "year": 2004}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 1.0, "year": 2004}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2004}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 2.0, "year": 2004}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 1.0, "year": 2004}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2004}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 3.0, "year": 2004}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 3.0, "year": 2004}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2004}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2004}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2004}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2004}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2004}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2004}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2004}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 2.0, "year": 2004}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 3.0, "year": 2004}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2004}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 1.0, "year": 2004}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2004}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2004}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2004}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2004}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2004}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 2.0, "year": 2004}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2004}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 1.0, "year": 2004}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2004}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2004}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2004}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 1.0, "year": 2004}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2004}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2004}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2004}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 1.0, "year": 2004}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 2.0, "year": 2004}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2004}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2004}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2004}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2004}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 1.0, "year": 2004}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 1.0, "year": 2004}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 2.0, "year": 2004}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2004}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2004}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 1.0, "year": 2004}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2004}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2004}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2004}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2004}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2004}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2004}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2004}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2004}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2004}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2004}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2004}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2004}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 1.0, "year": 2004}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2004}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2004}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2004}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 2.0, "year": 2004}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2004}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2004}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 1.0, "year": 2004}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2004}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2004}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2004}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 1.0, "year": 2004}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2004}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2004}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 2.0, "year": 2004}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 1.0, "year": 2004}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2004}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2004}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2004}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2004}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 2.0, "year": 2004}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 3.0, "year": 2004}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2004}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2004}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2004}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 1.0, "year": 2004}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 7.0, "year": 2004}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 2.0, "year": 2004}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 3.0, "year": 2004}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 1.0, "year": 2004}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 2.0, "year": 2004}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 2.0, "year": 2004}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 1.0, "year": 2004}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 5.0, "year": 2004}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2004}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 4.0, "year": 2004}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 6.0, "year": 2004}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 2.0, "year": 2004}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 5.0, "year": 2004}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2004}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2004}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2004}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2004}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 1.0, "year": 2004}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 1.0, "year": 2004}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2004}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 1.0, "year": 2004}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2004}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2004}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 1.0, "year": 2004}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2004}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2004}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2004}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 2.0, "year": 2004}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2004}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2004}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 1.0, "year": 2004}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2004}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 1.0, "year": 2004}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2004}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 1.0, "year": 2004}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2004}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2004}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2004}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2004}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2004}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2004}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 2.0, "year": 2004}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2004}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2004}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2004}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2004}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 1.0, "year": 2004}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2004}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2004}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2004}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2004}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 1.0, "year": 2004}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2004}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2004}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2004}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2004}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 2.0, "year": 2004}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2004}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2004}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2004}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2004}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2004}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2004}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 1.0, "year": 2004}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2004}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2004}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2004}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2004}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 1.0, "year": 2004}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 1.0, "year": 2004}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 1.0, "year": 2004}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2004}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2004}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 1.0, "year": 2004}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2004}]}, {"2005": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2005}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 1.0, "year": 2005}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2005}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 6.0, "year": 2005}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2005}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2005}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 3.0, "year": 2005}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2005}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2005}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 1.0, "year": 2005}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 4.0, "year": 2005}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2005}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 2.0, "year": 2005}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2005}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 3.0, "year": 2005}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2005}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 1.0, "year": 2005}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 4.0, "year": 2005}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 10.0, "year": 2005}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2005}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2005}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 4.0, "year": 2005}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 2.0, "year": 2005}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 3.0, "year": 2005}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 1.0, "year": 2005}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 2.0, "year": 2005}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 4.0, "year": 2005}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2005}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2005}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2005}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2005}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2005}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2005}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2005}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2005}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 2.0, "year": 2005}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 3.0, "year": 2005}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2005}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 1.0, "year": 2005}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 3.0, "year": 2005}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2005}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2005}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2005}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 8.0, "year": 2005}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2005}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 1.0, "year": 2005}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2005}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 1.0, "year": 2005}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2005}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 5.0, "year": 2005}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 2.0, "year": 2005}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2005}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2005}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 3.0, "year": 2005}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2005}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2005}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2005}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2005}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2005}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2005}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2005}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 2.0, "year": 2005}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2005}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2005}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2005}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2005}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2005}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2005}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 2.0, "year": 2005}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2005}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2005}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2005}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2005}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2005}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2005}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2005}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2005}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2005}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2005}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2005}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2005}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 3.0, "year": 2005}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 1.0, "year": 2005}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2005}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2005}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2005}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2005}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2005}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2005}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2005}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 7.0, "year": 2005}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2005}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 2.0, "year": 2005}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 2.0, "year": 2005}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 1.0, "year": 2005}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 2.0, "year": 2005}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2005}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 3.0, "year": 2005}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 3.0, "year": 2005}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2005}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2005}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2005}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2005}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2005}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2005}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2005}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 2.0, "year": 2005}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 3.0, "year": 2005}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2005}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2005}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 1.0, "year": 2005}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2005}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2005}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2005}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2005}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2005}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2005}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2005}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 2.0, "year": 2005}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2005}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2005}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 1.0, "year": 2005}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2005}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2005}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 2.0, "year": 2005}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2005}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2005}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2005}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 2.0, "year": 2005}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2005}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2005}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2005}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2005}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 2.0, "year": 2005}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2005}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2005}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2005}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 5.0, "year": 2005}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2005}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2005}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2005}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2005}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 2.0, "year": 2005}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2005}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2005}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2005}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2005}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2005}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2005}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2005}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2005}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2005}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2005}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2005}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2005}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 2.0, "year": 2005}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2005}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2005}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2005}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2005}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2005}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 3.0, "year": 2005}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2005}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2005}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2005}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 1.0, "year": 2005}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2005}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 1.0, "year": 2005}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2005}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2005}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2005}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 2.0, "year": 2005}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 1.0, "year": 2005}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2005}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2005}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2005}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 1.0, "year": 2005}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2005}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 2.0, "year": 2005}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 1.0, "year": 2005}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 1.0, "year": 2005}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 1.0, "year": 2005}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 4.0, "year": 2005}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2005}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2005}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2005}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 1.0, "year": 2005}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 7.0, "year": 2005}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 2.0, "year": 2005}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 4.0, "year": 2005}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 1.0, "year": 2005}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 2.0, "year": 2005}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 4.0, "year": 2005}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 1.0, "year": 2005}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 5.0, "year": 2005}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2005}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 5.0, "year": 2005}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2005}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 1.0, "year": 2005}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 1.0, "year": 2005}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 6.0, "year": 2005}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 2.0, "year": 2005}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 6.0, "year": 2005}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2005}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2005}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2005}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2005}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 1.0, "year": 2005}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2005}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 1.0, "year": 2005}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2005}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 2.0, "year": 2005}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2005}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2005}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2005}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2005}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2005}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2005}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2005}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2005}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2005}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 2.0, "year": 2005}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2005}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2005}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 1.0, "year": 2005}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2005}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2005}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 1.0, "year": 2005}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2005}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 2.0, "year": 2005}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 1.0, "year": 2005}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2005}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2005}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2005}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2005}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2005}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2005}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 2.0, "year": 2005}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2005}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2005}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2005}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2005}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2005}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2005}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2005}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 2.0, "year": 2005}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 1.0, "year": 2005}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 1.0, "year": 2005}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 2.0, "year": 2005}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2005}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2005}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2005}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2005}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2005}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 2.0, "year": 2005}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2005}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2005}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2005}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2005}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2005}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2005}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 2.0, "year": 2005}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2005}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2005}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2005}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 1.0, "year": 2005}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2005}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2005}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2005}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2005}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2005}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 1.0, "year": 2005}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2005}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 1.0, "year": 2005}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 2.0, "year": 2005}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2005}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2005}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2005}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 2.0, "year": 2005}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2005}]}, {"2006": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2006}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 1.0, "year": 2006}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2006}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 7.0, "year": 2006}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2006}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2006}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 3.0, "year": 2006}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2006}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2006}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2006}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 4.0, "year": 2006}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2006}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 2.0, "year": 2006}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2006}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 3.0, "year": 2006}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2006}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 1.0, "year": 2006}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 4.0, "year": 2006}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 11.0, "year": 2006}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2006}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2006}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 4.0, "year": 2006}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 2.0, "year": 2006}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 3.0, "year": 2006}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 1.0, "year": 2006}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 2.0, "year": 2006}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 4.0, "year": 2006}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2006}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2006}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2006}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2006}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2006}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2006}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2006}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2006}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2006}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 2.0, "year": 2006}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 3.0, "year": 2006}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2006}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 1.0, "year": 2006}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2006}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 3.0, "year": 2006}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2006}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2006}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2006}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2006}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 11.0, "year": 2006}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2006}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 2.0, "year": 2006}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2006}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2006}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 1.0, "year": 2006}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2006}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2006}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 5.0, "year": 2006}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 2.0, "year": 2006}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2006}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2006}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 3.0, "year": 2006}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2006}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2006}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2006}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2006}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2006}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2006}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2006}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2006}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 2.0, "year": 2006}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2006}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2006}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2006}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2006}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2006}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2006}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2006}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 2.0, "year": 2006}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2006}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2006}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2006}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2006}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2006}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2006}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2006}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2006}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2006}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2006}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2006}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2006}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2006}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2006}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 1.0, "year": 2006}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 5.0, "year": 2006}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2006}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 2.0, "year": 2006}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 1.0, "year": 2006}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2006}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2006}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2006}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2006}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2006}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2006}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2006}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 7.0, "year": 2006}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2006}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 3.0, "year": 2006}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 2.0, "year": 2006}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 1.0, "year": 2006}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2006}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 2.0, "year": 2006}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2006}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 1.0, "year": 2006}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2006}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 3.0, "year": 2006}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 3.0, "year": 2006}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2006}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2006}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2006}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 2.0, "year": 2006}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2006}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2006}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2006}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 2.0, "year": 2006}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2006}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 1.0, "year": 2006}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 3.0, "year": 2006}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2006}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2006}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 1.0, "year": 2006}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2006}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2006}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2006}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2006}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2006}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2006}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2006}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 2.0, "year": 2006}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2006}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2006}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 1.0, "year": 2006}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2006}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 1.0, "year": 2006}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2006}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 2.0, "year": 2006}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2006}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2006}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2006}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 1.0, "year": 2006}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 2.0, "year": 2006}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2006}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2006}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2006}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2006}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2006}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 2.0, "year": 2006}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 1.0, "year": 2006}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2006}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2006}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2006}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 5.0, "year": 2006}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2006}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2006}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2006}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2006}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2006}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 2.0, "year": 2006}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2006}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2006}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2006}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2006}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2006}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2006}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2006}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2006}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2006}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2006}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2006}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2006}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2006}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2006}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2006}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 2.0, "year": 2006}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2006}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2006}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2006}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2006}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2006}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 3.0, "year": 2006}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2006}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2006}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2006}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 1.0, "year": 2006}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 2.0, "year": 2006}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2006}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2006}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 1.0, "year": 2006}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 1.0, "year": 2006}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 1.0, "year": 2006}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2006}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2006}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 1.0, "year": 2006}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2006}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 2.0, "year": 2006}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 1.0, "year": 2006}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2006}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2006}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 1.0, "year": 2006}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2006}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 1.0, "year": 2006}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2006}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 2.0, "year": 2006}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 3.0, "year": 2006}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2006}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2006}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 3.0, "year": 2006}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 4.0, "year": 2006}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2006}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2006}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2006}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 4.0, "year": 2006}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 7.0, "year": 2006}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 2.0, "year": 2006}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 5.0, "year": 2006}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 3.0, "year": 2006}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 2.0, "year": 2006}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 5.0, "year": 2006}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2006}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 1.0, "year": 2006}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 6.0, "year": 2006}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2006}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 5.0, "year": 2006}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2006}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2006}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 3.0, "year": 2006}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 7.0, "year": 2006}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 2.0, "year": 2006}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 6.0, "year": 2006}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2006}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2006}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2006}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2006}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 1.0, "year": 2006}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2006}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 1.0, "year": 2006}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2006}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 2.0, "year": 2006}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2006}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2006}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2006}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2006}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2006}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2006}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2006}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 1.0, "year": 2006}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2006}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2006}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 2.0, "year": 2006}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2006}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2006}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 1.0, "year": 2006}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2006}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 2.0, "year": 2006}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2006}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 2.0, "year": 2006}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2006}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 2.0, "year": 2006}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2006}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 1.0, "year": 2006}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2006}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2006}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2006}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2006}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2006}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2006}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2006}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2006}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2006}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 2.0, "year": 2006}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2006}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2006}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2006}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2006}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2006}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2006}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2006}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2006}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 2.0, "year": 2006}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 1.0, "year": 2006}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 1.0, "year": 2006}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 2.0, "year": 2006}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2006}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 1.0, "year": 2006}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2006}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2006}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2006}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2006}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 3.0, "year": 2006}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2006}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 1.0, "year": 2006}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2006}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2006}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2006}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2006}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2006}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 2.0, "year": 2006}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2006}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2006}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 1.0, "year": 2006}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2006}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2006}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2006}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2006}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2006}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2006}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2006}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2006}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 1.0, "year": 2006}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 2.0, "year": 2006}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2006}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2006}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2006}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2006}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2006}]}, {"2007": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2007}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 1.0, "year": 2007}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2007}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 1.0, "year": 2007}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 7.0, "year": 2007}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2007}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2007}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 3.0, "year": 2007}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2007}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2007}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2007}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2007}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2007}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 4.0, "year": 2007}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2007}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 2.0, "year": 2007}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2007}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 3.0, "year": 2007}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2007}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 1.0, "year": 2007}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 4.0, "year": 2007}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 11.0, "year": 2007}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2007}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2007}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2007}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 2.0, "year": 2007}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 3.0, "year": 2007}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 1.0, "year": 2007}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 5.0, "year": 2007}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 5.0, "year": 2007}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2007}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2007}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2007}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 3.0, "year": 2007}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2007}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2007}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2007}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2007}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2007}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 3.0, "year": 2007}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 5.0, "year": 2007}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2007}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 1.0, "year": 2007}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2007}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 4.0, "year": 2007}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2007}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2007}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2007}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2007}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 1.0, "year": 2007}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 12.0, "year": 2007}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 1.0, "year": 2007}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2007}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 3.0, "year": 2007}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2007}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 1.0, "year": 2007}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2007}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 1.0, "year": 2007}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2007}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2007}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 5.0, "year": 2007}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 2.0, "year": 2007}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2007}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 3.0, "year": 2007}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2007}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2007}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2007}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2007}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2007}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2007}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2007}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2007}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 2.0, "year": 2007}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2007}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2007}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2007}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2007}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2007}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2007}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 2.0, "year": 2007}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2007}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2007}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2007}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2007}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2007}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2007}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2007}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2007}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2007}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2007}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2007}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2007}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2007}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2007}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2007}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 6.0, "year": 2007}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2007}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2007}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 1.0, "year": 2007}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2007}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2007}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2007}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2007}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2007}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2007}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2007}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 1.0, "year": 2007}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 8.0, "year": 2007}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2007}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2007}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2007}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 3.0, "year": 2007}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 2.0, "year": 2007}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2007}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2007}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 3.0, "year": 2007}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 1.0, "year": 2007}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2007}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 1.0, "year": 2007}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2007}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2007}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 4.0, "year": 2007}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 4.0, "year": 2007}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2007}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2007}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2007}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2007}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 2.0, "year": 2007}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 1.0, "year": 2007}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2007}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2007}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2007}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 2.0, "year": 2007}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2007}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 1.0, "year": 2007}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 4.0, "year": 2007}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2007}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2007}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 1.0, "year": 2007}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2007}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2007}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2007}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2007}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2007}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 1.0, "year": 2007}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 1.0, "year": 2007}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2007}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 2.0, "year": 2007}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2007}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 1.0, "year": 2007}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2007}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 1.0, "year": 2007}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2007}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 2.0, "year": 2007}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2007}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2007}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2007}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 1.0, "year": 2007}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2007}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2007}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2007}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2007}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2007}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 2.0, "year": 2007}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 2.0, "year": 2007}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2007}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2007}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 1.0, "year": 2007}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2007}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 5.0, "year": 2007}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2007}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2007}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2007}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 3.0, "year": 2007}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2007}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2007}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 3.0, "year": 2007}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2007}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2007}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2007}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2007}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2007}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2007}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2007}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2007}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2007}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2007}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2007}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2007}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2007}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2007}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2007}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2007}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 2.0, "year": 2007}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2007}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2007}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2007}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2007}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 3.0, "year": 2007}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2007}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2007}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2007}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2007}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2007}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2007}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2007}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2007}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 1.0, "year": 2007}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 1.0, "year": 2007}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2007}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2007}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2007}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2007}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 3.0, "year": 2007}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 1.0, "year": 2007}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2007}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2007}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2007}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2007}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2007}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2007}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 1.0, "year": 2007}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 2.0, "year": 2007}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2007}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 2.0, "year": 2007}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 3.0, "year": 2007}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2007}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2007}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 3.0, "year": 2007}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 1.0, "year": 2007}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 4.0, "year": 2007}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2007}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2007}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2007}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 5.0, "year": 2007}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 7.0, "year": 2007}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2007}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 5.0, "year": 2007}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 3.0, "year": 2007}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 3.0, "year": 2007}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 5.0, "year": 2007}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 2.0, "year": 2007}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2007}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 1.0, "year": 2007}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 9.0, "year": 2007}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2007}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 5.0, "year": 2007}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2007}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 3.0, "year": 2007}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 8.0, "year": 2007}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 2.0, "year": 2007}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 8.0, "year": 2007}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2007}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2007}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2007}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2007}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2007}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 1.0, "year": 2007}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2007}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 1.0, "year": 2007}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2007}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 2.0, "year": 2007}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2007}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2007}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 2.0, "year": 2007}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2007}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2007}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2007}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2007}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 1.0, "year": 2007}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2007}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2007}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2007}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2007}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2007}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2007}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2007}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2007}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2007}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2007}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 3.0, "year": 2007}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2007}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 2.0, "year": 2007}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2007}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 2.0, "year": 2007}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2007}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 1.0, "year": 2007}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2007}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2007}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2007}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2007}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2007}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2007}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2007}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2007}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2007}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2007}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 2.0, "year": 2007}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2007}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 1.0, "year": 2007}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2007}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2007}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2007}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2007}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2007}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2007}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2007}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2007}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 2.0, "year": 2007}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 1.0, "year": 2007}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 1.0, "year": 2007}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 2.0, "year": 2007}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2007}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 3.0, "year": 2007}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 1.0, "year": 2007}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2007}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2007}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2007}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2007}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 3.0, "year": 2007}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2007}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 1.0, "year": 2007}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2007}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2007}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2007}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2007}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2007}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2007}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 3.0, "year": 2007}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2007}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2007}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 1.0, "year": 2007}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2007}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2007}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2007}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2007}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2007}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2007}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2007}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2007}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2007}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 1.0, "year": 2007}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 2.0, "year": 2007}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2007}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2007}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2007}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2007}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2007}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2007}]}, {"2008": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2008}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 1.0, "year": 2008}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2008}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 2.0, "year": 2008}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 7.0, "year": 2008}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2008}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2008}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 3.0, "year": 2008}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2008}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2008}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2008}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2008}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2008}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 6.0, "year": 2008}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2008}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 2.0, "year": 2008}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2008}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 3.0, "year": 2008}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2008}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2008}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 1.0, "year": 2008}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 5.0, "year": 2008}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2008}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 13.0, "year": 2008}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2008}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2008}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2008}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 2.0, "year": 2008}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 3.0, "year": 2008}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 1.0, "year": 2008}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 7.0, "year": 2008}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 1.0, "year": 2008}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 5.0, "year": 2008}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2008}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2008}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2008}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 3.0, "year": 2008}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2008}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2008}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2008}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2008}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2008}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 3.0, "year": 2008}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 1.0, "year": 2008}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 5.0, "year": 2008}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2008}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 2.0, "year": 2008}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2008}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 4.0, "year": 2008}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2008}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2008}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2008}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2008}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 1.0, "year": 2008}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 12.0, "year": 2008}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 1.0, "year": 2008}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2008}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 3.0, "year": 2008}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2008}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 1.0, "year": 2008}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2008}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 1.0, "year": 2008}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2008}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2008}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 5.0, "year": 2008}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 2.0, "year": 2008}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2008}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 3.0, "year": 2008}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2008}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2008}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2008}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2008}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2008}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2008}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2008}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 2.0, "year": 2008}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2008}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2008}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2008}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2008}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2008}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2008}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 2.0, "year": 2008}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2008}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2008}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2008}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2008}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2008}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2008}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2008}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2008}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2008}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2008}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2008}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2008}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2008}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2008}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 6.0, "year": 2008}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2008}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 1.0, "year": 2008}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2008}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2008}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2008}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2008}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2008}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2008}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2008}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 1.0, "year": 2008}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 10.0, "year": 2008}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2008}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2008}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2008}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 3.0, "year": 2008}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 2.0, "year": 2008}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2008}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2008}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2008}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 4.0, "year": 2008}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 1.0, "year": 2008}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2008}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 2.0, "year": 2008}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2008}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2008}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 5.0, "year": 2008}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 4.0, "year": 2008}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2008}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2008}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2008}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2008}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 2.0, "year": 2008}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2008}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2008}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2008}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 2.0, "year": 2008}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2008}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 1.0, "year": 2008}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 4.0, "year": 2008}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2008}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2008}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 1.0, "year": 2008}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2008}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2008}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2008}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2008}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2008}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 1.0, "year": 2008}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 1.0, "year": 2008}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2008}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 2.0, "year": 2008}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2008}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 1.0, "year": 2008}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2008}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 3.0, "year": 2008}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2008}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 2.0, "year": 2008}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2008}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2008}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2008}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 4.0, "year": 2008}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2008}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2008}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2008}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2008}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2008}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2008}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2008}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2008}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2008}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 2.0, "year": 2008}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 3.0, "year": 2008}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2008}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2008}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 1.0, "year": 2008}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2008}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 1.0, "year": 2008}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 5.0, "year": 2008}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2008}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2008}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2008}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2008}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2008}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2008}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2008}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 3.0, "year": 2008}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2008}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2008}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2008}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2008}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2008}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2008}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2008}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2008}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2008}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2008}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2008}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2008}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2008}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2008}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2008}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 2.0, "year": 2008}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2008}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2008}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2008}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2008}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 3.0, "year": 2008}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2008}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 2.0, "year": 2008}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2008}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2008}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2008}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2008}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2008}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2008}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2008}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 1.0, "year": 2008}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2008}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 2.0, "year": 2008}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2008}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2008}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2008}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2008}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2008}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 3.0, "year": 2008}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 1.0, "year": 2008}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2008}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2008}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2008}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2008}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2008}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2008}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2008}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 1.0, "year": 2008}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 1.0, "year": 2008}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 1.0, "year": 2008}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2008}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2008}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 2.0, "year": 2008}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2008}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2008}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2008}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 1.0, "year": 2008}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 3.0, "year": 2008}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2008}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2008}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 3.0, "year": 2008}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 1.0, "year": 2008}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 1.0, "year": 2008}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 5.0, "year": 2008}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2008}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2008}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2008}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 5.0, "year": 2008}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 8.0, "year": 2008}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2008}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 7.0, "year": 2008}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 4.0, "year": 2008}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 3.0, "year": 2008}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 6.0, "year": 2008}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 2.0, "year": 2008}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2008}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 1.0, "year": 2008}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 9.0, "year": 2008}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2008}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 5.0, "year": 2008}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2008}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 3.0, "year": 2008}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 8.0, "year": 2008}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 3.0, "year": 2008}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 9.0, "year": 2008}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2008}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2008}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2008}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2008}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2008}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 2.0, "year": 2008}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2008}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 4.0, "year": 2008}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2008}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2008}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2008}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 2.0, "year": 2008}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2008}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2008}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 5.0, "year": 2008}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2008}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2008}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2008}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2008}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2008}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 2.0, "year": 2008}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2008}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2008}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2008}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2008}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2008}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 2.0, "year": 2008}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 2.0, "year": 2008}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2008}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2008}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2008}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2008}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2008}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2008}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2008}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 2.0, "year": 2008}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2008}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 2.0, "year": 2008}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2008}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 1.0, "year": 2008}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2008}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2008}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2008}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2008}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2008}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2008}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2008}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2008}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2008}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2008}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2008}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2008}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 3.0, "year": 2008}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2008}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 1.0, "year": 2008}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2008}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2008}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2008}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2008}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2008}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2008}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2008}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2008}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2008}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 2.0, "year": 2008}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 1.0, "year": 2008}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 2.0, "year": 2008}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2008}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2008}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 3.0, "year": 2008}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 1.0, "year": 2008}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2008}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2008}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2008}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2008}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2008}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 3.0, "year": 2008}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2008}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 1.0, "year": 2008}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2008}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2008}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2008}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2008}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2008}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2008}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2008}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2008}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 3.0, "year": 2008}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2008}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2008}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2008}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 1.0, "year": 2008}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2008}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2008}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2008}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 1.0, "year": 2008}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2008}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2008}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2008}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2008}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2008}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2008}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 2.0, "year": 2008}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 2.0, "year": 2008}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2008}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2008}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2008}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2008}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2008}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2008}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2008}]}, {"2009": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2009}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 1.0, "year": 2009}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2009}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 2.0, "year": 2009}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 7.0, "year": 2009}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2009}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2009}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 3.0, "year": 2009}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2009}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2009}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2009}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 2.0, "year": 2009}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2009}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 6.0, "year": 2009}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 1.0, "year": 2009}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 1.0, "year": 2009}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 2.0, "year": 2009}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2009}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 3.0, "year": 2009}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2009}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2009}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 3.0, "year": 2009}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 5.0, "year": 2009}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2009}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 14.0, "year": 2009}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 1.0, "year": 2009}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 1.0, "year": 2009}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2009}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 2.0, "year": 2009}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 3.0, "year": 2009}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 1.0, "year": 2009}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 7.0, "year": 2009}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 1.0, "year": 2009}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 5.0, "year": 2009}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2009}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2009}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 1.0, "year": 2009}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 3.0, "year": 2009}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2009}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2009}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2009}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2009}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2009}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2009}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2009}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 1.0, "year": 2009}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 5.0, "year": 2009}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2009}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 2.0, "year": 2009}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2009}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 4.0, "year": 2009}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2009}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2009}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2009}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2009}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2009}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 1.0, "year": 2009}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 13.0, "year": 2009}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 1.0, "year": 2009}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2009}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 4.0, "year": 2009}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2009}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 1.0, "year": 2009}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2009}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 2.0, "year": 2009}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2009}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2009}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 5.0, "year": 2009}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 2.0, "year": 2009}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2009}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2009}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 3.0, "year": 2009}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 2.0, "year": 2009}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2009}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2009}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2009}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2009}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2009}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2009}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 3.0, "year": 2009}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2009}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2009}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2009}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2009}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2009}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2009}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2009}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2009}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2009}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2009}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 2.0, "year": 2009}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2009}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2009}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2009}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2009}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2009}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2009}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2009}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2009}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2009}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2009}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2009}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2009}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2009}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2009}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 6.0, "year": 2009}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2009}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 1.0, "year": 2009}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2009}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2009}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2009}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2009}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2009}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2009}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2009}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2009}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2009}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 1.0, "year": 2009}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 11.0, "year": 2009}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2009}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2009}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2009}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2009}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 3.0, "year": 2009}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 2.0, "year": 2009}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2009}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2009}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2009}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 4.0, "year": 2009}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 1.0, "year": 2009}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2009}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2009}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 3.0, "year": 2009}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2009}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 1.0, "year": 2009}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 5.0, "year": 2009}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 4.0, "year": 2009}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2009}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2009}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2009}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2009}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2009}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 2.0, "year": 2009}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2009}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2009}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2009}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 2.0, "year": 2009}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2009}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2009}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2009}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 5.0, "year": 2009}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2009}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2009}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 1.0, "year": 2009}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2009}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2009}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2009}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2009}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2009}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2009}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 1.0, "year": 2009}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 1.0, "year": 2009}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 1.0, "year": 2009}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2009}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 2.0, "year": 2009}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2009}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 1.0, "year": 2009}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2009}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 3.0, "year": 2009}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2009}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 3.0, "year": 2009}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2009}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2009}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2009}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 5.0, "year": 2009}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2009}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2009}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 1.0, "year": 2009}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 1.0, "year": 2009}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2009}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2009}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2009}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2009}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2009}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2009}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 2.0, "year": 2009}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2009}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2009}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2009}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 3.0, "year": 2009}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 1.0, "year": 2009}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2009}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2009}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2009}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2009}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2009}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2009}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2009}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2009}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2009}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2009}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2009}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2009}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 3.0, "year": 2009}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2009}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2009}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2009}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2009}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2009}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2009}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2009}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2009}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2009}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2009}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2009}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2009}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2009}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2009}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2009}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 2.0, "year": 2009}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2009}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2009}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2009}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2009}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2009}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 4.0, "year": 2009}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2009}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 2.0, "year": 2009}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2009}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2009}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2009}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2009}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2009}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2009}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2009}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 1.0, "year": 2009}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2009}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 2.0, "year": 2009}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2009}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2009}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2009}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 1.0, "year": 2009}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 1.0, "year": 2009}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 5.0, "year": 2009}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 1.0, "year": 2009}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2009}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2009}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2009}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2009}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2009}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2009}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2009}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2009}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2009}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2009}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 2.0, "year": 2009}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2009}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 1.0, "year": 2009}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2009}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 2.0, "year": 2009}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2009}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2009}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2009}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2009}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2009}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 1.0, "year": 2009}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 4.0, "year": 2009}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2009}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2009}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 4.0, "year": 2009}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 1.0, "year": 2009}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 2.0, "year": 2009}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 6.0, "year": 2009}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2009}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2009}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2009}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 6.0, "year": 2009}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 8.0, "year": 2009}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2009}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 9.0, "year": 2009}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 4.0, "year": 2009}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 3.0, "year": 2009}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 8.0, "year": 2009}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 2.0, "year": 2009}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2009}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 1.0, "year": 2009}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 9.0, "year": 2009}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2009}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2009}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 5.0, "year": 2009}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2009}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2009}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 5.0, "year": 2009}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 8.0, "year": 2009}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 3.0, "year": 2009}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 9.0, "year": 2009}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2009}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2009}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2009}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2009}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2009}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2009}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2009}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 2.0, "year": 2009}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2009}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 4.0, "year": 2009}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2009}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2009}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2009}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 4.0, "year": 2009}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2009}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2009}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 5.0, "year": 2009}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2009}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2009}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2009}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2009}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2009}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2009}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 2.0, "year": 2009}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2009}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2009}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2009}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2009}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2009}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 2.0, "year": 2009}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2009}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 3.0, "year": 2009}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2009}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 2.0, "year": 2009}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2009}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2009}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2009}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 1.0, "year": 2009}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2009}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2009}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2009}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2009}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 2.0, "year": 2009}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2009}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 2.0, "year": 2009}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2009}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 1.0, "year": 2009}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2009}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2009}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2009}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2009}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2009}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2009}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2009}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2009}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2009}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2009}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2009}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2009}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2009}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2009}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 3.0, "year": 2009}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2009}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 1.0, "year": 2009}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2009}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2009}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2009}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2009}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2009}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2009}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2009}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2009}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2009}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 2.0, "year": 2009}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2009}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 2.0, "year": 2009}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 1.0, "year": 2009}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2009}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 3.0, "year": 2009}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 1.0, "year": 2009}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2009}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2009}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2009}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2009}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2009}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 3.0, "year": 2009}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2009}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2009}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2009}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2009}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2009}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2009}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2009}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2009}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2009}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2009}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2009}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 3.0, "year": 2009}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2009}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2009}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2009}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 1.0, "year": 2009}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2009}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2009}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2009}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 1.0, "year": 2009}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2009}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2009}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2009}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2009}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2009}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2009}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 2.0, "year": 2009}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 2.0, "year": 2009}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2009}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2009}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2009}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2009}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 1.0, "year": 2009}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2009}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2009}]}, {"2010": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2010}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 1.0, "year": 2010}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2010}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 2.0, "year": 2010}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 8.0, "year": 2010}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 1.0, "year": 2010}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2010}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2010}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 3.0, "year": 2010}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2010}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2010}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2010}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 2.0, "year": 2010}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2010}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 6.0, "year": 2010}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 2.0, "year": 2010}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 1.0, "year": 2010}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 3.0, "year": 2010}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2010}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 3.0, "year": 2010}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2010}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2010}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 3.0, "year": 2010}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 5.0, "year": 2010}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2010}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 15.0, "year": 2010}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 2.0, "year": 2010}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2010}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2010}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 2.0, "year": 2010}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 3.0, "year": 2010}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 2.0, "year": 2010}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 7.0, "year": 2010}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 1.0, "year": 2010}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 6.0, "year": 2010}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2010}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2010}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 2.0, "year": 2010}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 5.0, "year": 2010}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2010}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2010}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2010}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2010}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2010}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2010}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2010}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 1.0, "year": 2010}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 6.0, "year": 2010}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2010}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 2.0, "year": 2010}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2010}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2010}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 4.0, "year": 2010}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2010}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2010}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 1.0, "year": 2010}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2010}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2010}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2010}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2010}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 1.0, "year": 2010}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 17.0, "year": 2010}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 2.0, "year": 2010}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2010}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2010}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 4.0, "year": 2010}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 1.0, "year": 2010}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2010}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 1.0, "year": 2010}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 1.0, "year": 2010}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2010}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 2.0, "year": 2010}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 2.0, "year": 2010}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2010}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2010}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 5.0, "year": 2010}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 3.0, "year": 2010}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2010}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 1.0, "year": 2010}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 4.0, "year": 2010}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2010}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2010}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2010}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2010}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2010}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2010}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 3.0, "year": 2010}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2010}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2010}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2010}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2010}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2010}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2010}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2010}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2010}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2010}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2010}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 2.0, "year": 2010}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2010}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2010}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2010}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2010}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2010}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2010}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2010}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2010}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 2.0, "year": 2010}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2010}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2010}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2010}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2010}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2010}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2010}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2010}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 1.0, "year": 2010}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2010}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 7.0, "year": 2010}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2010}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2010}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 1.0, "year": 2010}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2010}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2010}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2010}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2010}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2010}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2010}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2010}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2010}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 1.0, "year": 2010}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 12.0, "year": 2010}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2010}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2010}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2010}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2010}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 4.0, "year": 2010}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 2.0, "year": 2010}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2010}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2010}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2010}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 4.0, "year": 2010}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2010}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2010}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 1.0, "year": 2010}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2010}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2010}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 3.0, "year": 2010}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2010}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 2.0, "year": 2010}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 5.0, "year": 2010}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 4.0, "year": 2010}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2010}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2010}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2010}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2010}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2010}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 2.0, "year": 2010}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2010}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2010}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2010}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2010}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2010}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2010}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2010}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2010}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 5.0, "year": 2010}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2010}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2010}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 1.0, "year": 2010}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2010}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2010}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2010}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2010}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2010}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2010}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 1.0, "year": 2010}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 1.0, "year": 2010}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 1.0, "year": 2010}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2010}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2010}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 3.0, "year": 2010}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2010}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 1.0, "year": 2010}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2010}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 3.0, "year": 2010}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2010}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 3.0, "year": 2010}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2010}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2010}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2010}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 5.0, "year": 2010}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2010}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2010}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 1.0, "year": 2010}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 2.0, "year": 2010}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2010}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2010}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2010}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2010}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2010}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2010}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2010}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2010}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2010}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2010}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2010}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2010}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2010}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2010}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2010}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2010}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2010}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2010}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2010}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2010}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2010}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2010}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2010}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2010}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2010}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 3.0, "year": 2010}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2010}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2010}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2010}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2010}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 1.0, "year": 2010}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2010}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2010}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2010}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2010}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2010}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2010}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2010}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2010}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2010}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2010}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2010}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2010}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 2.0, "year": 2010}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2010}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2010}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2010}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2010}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2010}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 4.0, "year": 2010}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2010}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 2.0, "year": 2010}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2010}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 1.0, "year": 2010}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2010}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2010}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2010}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2010}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2010}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2010}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 1.0, "year": 2010}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2010}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 2.0, "year": 2010}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2010}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2010}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2010}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 2.0, "year": 2010}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 6.0, "year": 2010}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 1.0, "year": 2010}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2010}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2010}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2010}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2010}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2010}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2010}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2010}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2010}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2010}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2010}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 2.0, "year": 2010}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2010}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2010}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2010}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 2.0, "year": 2010}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2010}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2010}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2010}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 4.0, "year": 2010}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2010}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2010}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 1.0, "year": 2010}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 4.0, "year": 2010}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2010}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2010}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 4.0, "year": 2010}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 1.0, "year": 2010}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 2.0, "year": 2010}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 6.0, "year": 2010}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2010}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2010}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2010}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 6.0, "year": 2010}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 9.0, "year": 2010}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2010}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 9.0, "year": 2010}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 5.0, "year": 2010}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 3.0, "year": 2010}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 9.0, "year": 2010}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 2.0, "year": 2010}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2010}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 2.0, "year": 2010}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 10.0, "year": 2010}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2010}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2010}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 5.0, "year": 2010}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2010}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2010}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 5.0, "year": 2010}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 8.0, "year": 2010}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 3.0, "year": 2010}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 10.0, "year": 2010}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 2.0, "year": 2010}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2010}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2010}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 1.0, "year": 2010}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2010}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2010}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2010}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2010}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2010}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2010}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 2.0, "year": 2010}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2010}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 4.0, "year": 2010}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2010}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2010}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2010}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 5.0, "year": 2010}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2010}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2010}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 5.0, "year": 2010}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2010}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2010}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2010}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2010}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2010}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2010}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 2.0, "year": 2010}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2010}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2010}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2010}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2010}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2010}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 2.0, "year": 2010}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2010}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 3.0, "year": 2010}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2010}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 2.0, "year": 2010}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2010}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2010}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2010}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 1.0, "year": 2010}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2010}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2010}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2010}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2010}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 2.0, "year": 2010}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2010}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 2.0, "year": 2010}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2010}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 1.0, "year": 2010}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2010}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2010}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2010}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2010}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2010}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2010}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 1.0, "year": 2010}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2010}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2010}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2010}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2010}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2010}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2010}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 1.0, "year": 2010}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2010}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2010}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2010}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 3.0, "year": 2010}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2010}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 1.0, "year": 2010}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2010}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2010}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 2.0, "year": 2010}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2010}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2010}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2010}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2010}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2010}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 2.0, "year": 2010}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2010}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 2.0, "year": 2010}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 2.0, "year": 2010}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2010}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 4.0, "year": 2010}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2010}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2010}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2010}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2010}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2010}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 3.0, "year": 2010}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2010}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2010}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2010}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2010}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2010}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2010}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2010}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2010}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2010}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2010}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2010}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2010}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 3.0, "year": 2010}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2010}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2010}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2010}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2010}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 1.0, "year": 2010}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2010}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2010}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2010}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 1.0, "year": 2010}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2010}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2010}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2010}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2010}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2010}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2010}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2010}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 3.0, "year": 2010}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2010}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2010}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2010}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2010}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2010}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 2.0, "year": 2010}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2010}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2010}]}, {"2011": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2011}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 1.0, "year": 2011}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2011}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 2.0, "year": 2011}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 9.0, "year": 2011}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 1.0, "year": 2011}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2011}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2011}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 5.0, "year": 2011}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2011}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2011}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 3.0, "year": 2011}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 2.0, "year": 2011}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2011}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 7.0, "year": 2011}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 2.0, "year": 2011}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 1.0, "year": 2011}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 5.0, "year": 2011}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2011}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 5.0, "year": 2011}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2011}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2011}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 3.0, "year": 2011}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 5.0, "year": 2011}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2011}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 15.0, "year": 2011}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 2.0, "year": 2011}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2011}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2011}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 1.0, "year": 2011}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 3.0, "year": 2011}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 3.0, "year": 2011}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 2.0, "year": 2011}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 7.0, "year": 2011}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2011}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 8.0, "year": 2011}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2011}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2011}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 2.0, "year": 2011}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 7.0, "year": 2011}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2011}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2011}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 2.0, "year": 2011}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2011}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2011}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2011}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2011}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2011}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 1.0, "year": 2011}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 6.0, "year": 2011}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2011}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 2.0, "year": 2011}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2011}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2011}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 4.0, "year": 2011}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2011}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2011}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 1.0, "year": 2011}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2011}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2011}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2011}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2011}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 1.0, "year": 2011}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 20.0, "year": 2011}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 2.0, "year": 2011}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2011}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 4.0, "year": 2011}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 1.0, "year": 2011}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2011}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 1.0, "year": 2011}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 1.0, "year": 2011}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2011}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2011}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 2.0, "year": 2011}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2011}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2011}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 1.0, "year": 2011}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 6.0, "year": 2011}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 3.0, "year": 2011}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2011}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2011}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 4.0, "year": 2011}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2011}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2011}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2011}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2011}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2011}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2011}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2011}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 3.0, "year": 2011}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2011}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2011}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2011}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2011}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2011}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2011}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2011}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2011}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 2.0, "year": 2011}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2011}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2011}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2011}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2011}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2011}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2011}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2011}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2011}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 3.0, "year": 2011}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2011}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2011}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2011}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2011}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2011}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2011}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2011}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2011}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2011}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 12.0, "year": 2011}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 2.0, "year": 2011}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2011}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2011}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 1.0, "year": 2011}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2011}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2011}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 2.0, "year": 2011}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2011}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2011}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2011}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2011}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2011}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2011}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2011}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 1.0, "year": 2011}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 13.0, "year": 2011}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2011}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2011}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2011}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2011}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 4.0, "year": 2011}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 2.0, "year": 2011}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2011}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2011}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 6.0, "year": 2011}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2011}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2011}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2011}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 1.0, "year": 2011}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 2.0, "year": 2011}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2011}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2011}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 3.0, "year": 2011}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2011}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 2.0, "year": 2011}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 5.0, "year": 2011}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 4.0, "year": 2011}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2011}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 3.0, "year": 2011}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2011}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2011}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2011}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2011}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 2.0, "year": 2011}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2011}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2011}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2011}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2011}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2011}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2011}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2011}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2011}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 6.0, "year": 2011}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2011}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2011}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2011}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2011}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2011}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2011}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2011}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2011}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2011}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 1.0, "year": 2011}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 2.0, "year": 2011}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2011}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 2.0, "year": 2011}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2011}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 2.0, "year": 2011}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2011}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2011}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 3.0, "year": 2011}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2011}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 3.0, "year": 2011}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2011}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 6.0, "year": 2011}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2011}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2011}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2011}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2011}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2011}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 6.0, "year": 2011}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 2.0, "year": 2011}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2011}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2011}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 1.0, "year": 2011}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 2.0, "year": 2011}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2011}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2011}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2011}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2011}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2011}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2011}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2011}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2011}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2011}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2011}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2011}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2011}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2011}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2011}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2011}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2011}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2011}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2011}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2011}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2011}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2011}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2011}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2011}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 4.0, "year": 2011}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2011}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2011}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2011}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2011}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 1.0, "year": 2011}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 1.0, "year": 2011}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2011}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2011}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2011}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2011}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2011}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2011}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2011}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2011}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2011}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 2.0, "year": 2011}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2011}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2011}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2011}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2011}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2011}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2011}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 1.0, "year": 2011}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2011}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2011}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2011}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2011}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2011}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 1.0, "year": 2011}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2011}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2011}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2011}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2011}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2011}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2011}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2011}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 1.0, "year": 2011}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2011}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 2.0, "year": 2011}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2011}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2011}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2011}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 2.0, "year": 2011}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 6.0, "year": 2011}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 2.0, "year": 2011}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2011}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2011}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2011}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2011}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2011}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2011}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2011}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2011}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 1.0, "year": 2011}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2011}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2011}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2011}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 2.0, "year": 2011}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2011}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2011}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2011}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 2.0, "year": 2011}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2011}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2011}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2011}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 5.0, "year": 2011}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2011}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2011}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 2.0, "year": 2011}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 5.0, "year": 2011}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2011}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 1.0, "year": 2011}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 1.0, "year": 2011}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2011}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 6.0, "year": 2011}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 1.0, "year": 2011}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 2.0, "year": 2011}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 9.0, "year": 2011}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2011}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2011}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2011}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 8.0, "year": 2011}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 9.0, "year": 2011}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2011}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 11.0, "year": 2011}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 6.0, "year": 2011}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 1.0, "year": 2011}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2011}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 11.0, "year": 2011}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 4.0, "year": 2011}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 1.0, "year": 2011}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2011}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 2.0, "year": 2011}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 10.0, "year": 2011}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2011}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2011}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 5.0, "year": 2011}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2011}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2011}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 6.0, "year": 2011}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 9.0, "year": 2011}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 4.0, "year": 2011}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 10.0, "year": 2011}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 3.0, "year": 2011}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2011}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2011}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2011}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2011}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2011}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2011}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2011}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 2.0, "year": 2011}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2011}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 4.0, "year": 2011}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2011}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2011}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2011}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 6.0, "year": 2011}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 2.0, "year": 2011}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2011}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 9.0, "year": 2011}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2011}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2011}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2011}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 2.0, "year": 2011}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2011}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 2.0, "year": 2011}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2011}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2011}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2011}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2011}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2011}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 2.0, "year": 2011}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2011}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 4.0, "year": 2011}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2011}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 4.0, "year": 2011}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2011}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2011}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2011}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 1.0, "year": 2011}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2011}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2011}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2011}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2011}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 2.0, "year": 2011}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2011}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2011}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 2.0, "year": 2011}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 1.0, "year": 2011}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 1.0, "year": 2011}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2011}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2011}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2011}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2011}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2011}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2011}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2011}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2011}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2011}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2011}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2011}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 2.0, "year": 2011}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2011}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2011}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2011}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 3.0, "year": 2011}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2011}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 1.0, "year": 2011}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2011}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2011}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 2.0, "year": 2011}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2011}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2011}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2011}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2011}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2011}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 2.0, "year": 2011}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2011}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 2.0, "year": 2011}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 2.0, "year": 2011}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 4.0, "year": 2011}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2011}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2011}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 1.0, "year": 2011}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2011}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2011}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2011}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 4.0, "year": 2011}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2011}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2011}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2011}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2011}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2011}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2011}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2011}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2011}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 3.0, "year": 2011}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2011}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2011}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 4.0, "year": 2011}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2011}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2011}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2011}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 1.0, "year": 2011}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2011}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2011}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2011}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 1.0, "year": 2011}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2011}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2011}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2011}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2011}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2011}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2011}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2011}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2011}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 3.0, "year": 2011}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2011}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2011}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2011}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2011}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2011}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 1.0, "year": 2011}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 2.0, "year": 2011}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2011}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2011}]}, {"2012": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2012}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 1.0, "year": 2012}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2012}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 2.0, "year": 2012}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 10.0, "year": 2012}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2012}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2012}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2012}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 5.0, "year": 2012}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2012}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2012}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 5.0, "year": 2012}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 3.0, "year": 2012}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2012}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 7.0, "year": 2012}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 2.0, "year": 2012}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 1.0, "year": 2012}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 5.0, "year": 2012}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2012}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 5.0, "year": 2012}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2012}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2012}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 3.0, "year": 2012}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 6.0, "year": 2012}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2012}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 17.0, "year": 2012}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 2.0, "year": 2012}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2012}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2012}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 1.0, "year": 2012}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 6.0, "year": 2012}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 4.0, "year": 2012}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 2.0, "year": 2012}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 8.0, "year": 2012}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2012}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 9.0, "year": 2012}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2012}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2012}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 3.0, "year": 2012}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 7.0, "year": 2012}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2012}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 2.0, "year": 2012}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 4.0, "year": 2012}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2012}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2012}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2012}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2012}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 7.0, "year": 2012}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2012}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 2.0, "year": 2012}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2012}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2012}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 4.0, "year": 2012}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2012}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2012}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 1.0, "year": 2012}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2012}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2012}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2012}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2012}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2012}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 1.0, "year": 2012}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 21.0, "year": 2012}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 2.0, "year": 2012}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2012}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 4.0, "year": 2012}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 1.0, "year": 2012}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2012}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 1.0, "year": 2012}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 1.0, "year": 2012}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2012}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2012}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 2.0, "year": 2012}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2012}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2012}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 2.0, "year": 2012}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 6.0, "year": 2012}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2012}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 4.0, "year": 2012}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2012}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2012}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 4.0, "year": 2012}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2012}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2012}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2012}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2012}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2012}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2012}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2012}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 3.0, "year": 2012}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2012}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2012}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2012}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2012}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2012}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2012}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2012}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 4.0, "year": 2012}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2012}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2012}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2012}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 2.0, "year": 2012}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2012}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2012}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2012}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2012}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2012}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 3.0, "year": 2012}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2012}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2012}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2012}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2012}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2012}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2012}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2012}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2012}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2012}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 15.0, "year": 2012}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2012}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2012}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2012}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2012}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2012}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2012}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2012}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2012}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2012}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2012}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2012}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2012}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2012}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 1.0, "year": 2012}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 14.0, "year": 2012}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2012}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2012}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2012}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2012}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 4.0, "year": 2012}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 2.0, "year": 2012}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2012}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2012}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 6.0, "year": 2012}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2012}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2012}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2012}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 1.0, "year": 2012}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 2.0, "year": 2012}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2012}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2012}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 3.0, "year": 2012}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 2.0, "year": 2012}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 5.0, "year": 2012}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 4.0, "year": 2012}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2012}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2012}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 4.0, "year": 2012}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2012}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2012}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2012}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2012}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2012}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 2.0, "year": 2012}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2012}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2012}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2012}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2012}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2012}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2012}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2012}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2012}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 7.0, "year": 2012}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2012}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2012}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2012}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2012}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 3.0, "year": 2012}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2012}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2012}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2012}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2012}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2012}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2012}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 1.0, "year": 2012}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2012}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 1.0, "year": 2012}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 2.0, "year": 2012}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2012}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2012}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 2.0, "year": 2012}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2012}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2012}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 3.0, "year": 2012}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2012}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 3.0, "year": 2012}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2012}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 6.0, "year": 2012}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2012}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2012}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2012}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2012}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2012}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 6.0, "year": 2012}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 2.0, "year": 2012}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2012}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2012}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 1.0, "year": 2012}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 2.0, "year": 2012}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2012}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2012}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2012}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2012}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2012}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2012}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2012}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2012}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2012}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2012}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2012}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2012}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2012}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2012}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2012}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2012}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2012}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2012}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2012}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2012}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2012}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2012}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 4.0, "year": 2012}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2012}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2012}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2012}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2012}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2012}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 2.0, "year": 2012}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2012}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2012}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2012}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2012}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2012}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2012}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2012}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2012}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2012}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2012}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2012}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2012}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2012}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2012}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 1.0, "year": 2012}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2012}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2012}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2012}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2012}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2012}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 1.0, "year": 2012}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2012}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2012}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2012}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2012}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2012}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2012}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2012}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2012}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2012}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2012}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 2.0, "year": 2012}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2012}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2012}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 2.0, "year": 2012}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 7.0, "year": 2012}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 3.0, "year": 2012}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2012}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2012}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2012}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2012}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2012}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2012}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2012}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2012}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2012}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 3.0, "year": 2012}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2012}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2012}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2012}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 2.0, "year": 2012}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2012}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2012}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2012}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 3.0, "year": 2012}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2012}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2012}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2012}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 7.0, "year": 2012}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2012}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2012}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 2.0, "year": 2012}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 7.0, "year": 2012}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2012}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 1.0, "year": 2012}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 1.0, "year": 2012}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2012}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 7.0, "year": 2012}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 1.0, "year": 2012}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 3.0, "year": 2012}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 9.0, "year": 2012}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2012}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2012}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 8.0, "year": 2012}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 1.0, "year": 2012}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2012}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2012}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 11.0, "year": 2012}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 6.0, "year": 2012}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 1.0, "year": 2012}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2012}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 12.0, "year": 2012}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 5.0, "year": 2012}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2012}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2012}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 3.0, "year": 2012}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 12.0, "year": 2012}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2012}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2012}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 6.0, "year": 2012}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2012}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2012}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 7.0, "year": 2012}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 9.0, "year": 2012}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 4.0, "year": 2012}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 10.0, "year": 2012}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 3.0, "year": 2012}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2012}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2012}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2012}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2012}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2012}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2012}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2012}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 2.0, "year": 2012}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2012}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 5.0, "year": 2012}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 1.0, "year": 2012}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2012}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2012}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 2.0, "year": 2012}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 7.0, "year": 2012}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2012}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2012}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2012}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2012}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2012}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2012}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2012}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 3.0, "year": 2012}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2012}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2012}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2012}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2012}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 2.0, "year": 2012}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2012}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 4.0, "year": 2012}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2012}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 5.0, "year": 2012}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2012}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2012}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 4.0, "year": 2012}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2012}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2012}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2012}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2012}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 5.0, "year": 2012}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2012}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2012}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 2.0, "year": 2012}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 1.0, "year": 2012}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2012}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2012}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 2.0, "year": 2012}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2012}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2012}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2012}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2012}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2012}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2012}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2012}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2012}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2012}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 2.0, "year": 2012}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2012}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2012}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 3.0, "year": 2012}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2012}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 3.0, "year": 2012}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2012}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2012}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2012}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 2.0, "year": 2012}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2012}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2012}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2012}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2012}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 2.0, "year": 2012}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2012}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 2.0, "year": 2012}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 3.0, "year": 2012}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 1.0, "year": 2012}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 4.0, "year": 2012}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2012}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 2.0, "year": 2012}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2012}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2012}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2012}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 4.0, "year": 2012}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2012}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2012}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2012}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2012}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2012}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2012}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2012}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 3.0, "year": 2012}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2012}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2012}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 4.0, "year": 2012}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2012}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2012}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2012}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 2.0, "year": 2012}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2012}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 2.0, "year": 2012}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2012}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 1.0, "year": 2012}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2012}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 1.0, "year": 2012}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2012}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2012}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2012}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2012}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 1.0, "year": 2012}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2012}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2012}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2012}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2012}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2012}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 3.0, "year": 2012}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2012}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2012}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2012}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2012}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2012}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2012}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 1.0, "year": 2012}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 2.0, "year": 2012}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2012}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2012}]}, {"2013": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2013}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2013}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2013}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 3.0, "year": 2013}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2013}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2013}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 10.0, "year": 2013}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2013}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2013}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2013}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 5.0, "year": 2013}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2013}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2013}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2013}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 1.0, "year": 2013}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2013}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 6.0, "year": 2013}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 3.0, "year": 2013}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2013}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 7.0, "year": 2013}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 2.0, "year": 2013}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 1.0, "year": 2013}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 5.0, "year": 2013}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2013}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 6.0, "year": 2013}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 3.0, "year": 2013}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2013}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 3.0, "year": 2013}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 1.0, "year": 2013}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 6.0, "year": 2013}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2013}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 17.0, "year": 2013}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 2.0, "year": 2013}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2013}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2013}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 2.0, "year": 2013}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 6.0, "year": 2013}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 6.0, "year": 2013}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 2.0, "year": 2013}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 9.0, "year": 2013}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2013}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 12.0, "year": 2013}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2013}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2013}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2013}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 3.0, "year": 2013}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 7.0, "year": 2013}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2013}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 2.0, "year": 2013}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 4.0, "year": 2013}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2013}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2013}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2013}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2013}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 8.0, "year": 2013}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2013}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 2.0, "year": 2013}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2013}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2013}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 5.0, "year": 2013}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2013}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2013}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2013}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 1.0, "year": 2013}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2013}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2013}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2013}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2013}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2013}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 1.0, "year": 2013}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 23.0, "year": 2013}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 2.0, "year": 2013}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2013}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 5.0, "year": 2013}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2013}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 2.0, "year": 2013}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 1.0, "year": 2013}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2013}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 1.0, "year": 2013}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 2.0, "year": 2013}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2013}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2013}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 2.0, "year": 2013}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 7.0, "year": 2013}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2013}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 4.0, "year": 2013}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2013}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2013}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 4.0, "year": 2013}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2013}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2013}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2013}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2013}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2013}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2013}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2013}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2013}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 3.0, "year": 2013}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2013}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2013}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2013}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2013}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2013}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2013}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2013}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 4.0, "year": 2013}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2013}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2013}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 2.0, "year": 2013}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 2.0, "year": 2013}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2013}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2013}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2013}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2013}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2013}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 3.0, "year": 2013}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2013}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2013}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 1.0, "year": 2013}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2013}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2013}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2013}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 1.0, "year": 2013}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2013}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2013}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 16.0, "year": 2013}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2013}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2013}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2013}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2013}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2013}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2013}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2013}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2013}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2013}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2013}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 1.0, "year": 2013}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2013}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2013}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2013}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2013}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 1.0, "year": 2013}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 17.0, "year": 2013}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2013}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2013}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2013}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2013}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2013}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 2.0, "year": 2013}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2013}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2013}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2013}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2013}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2013}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2013}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 1.0, "year": 2013}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 3.0, "year": 2013}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2013}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2013}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2013}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 2.0, "year": 2013}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2013}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 4.0, "year": 2013}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2013}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2013}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2013}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 5.0, "year": 2013}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2013}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2013}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2013}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 1.0, "year": 2013}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2013}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2013}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2013}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2013}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2013}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 2.0, "year": 2013}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2013}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2013}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2013}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2013}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2013}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2013}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2013}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 8.0, "year": 2013}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 1.0, "year": 2013}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 1.0, "year": 2013}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 1.0, "year": 2013}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2013}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2013}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2013}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2013}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 3.0, "year": 2013}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 1.0, "year": 2013}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2013}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2013}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2013}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2013}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2013}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 1.0, "year": 2013}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 1.0, "year": 2013}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2013}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 1.0, "year": 2013}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 2.0, "year": 2013}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2013}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2013}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 2.0, "year": 2013}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2013}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2013}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 3.0, "year": 2013}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 2.0, "year": 2013}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 3.0, "year": 2013}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 4.0, "year": 2013}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 6.0, "year": 2013}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2013}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2013}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2013}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2013}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2013}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 6.0, "year": 2013}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 2.0, "year": 2013}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2013}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2013}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 1.0, "year": 2013}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 2.0, "year": 2013}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2013}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 1.0, "year": 2013}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 1.0, "year": 2013}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2013}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2013}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2013}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2013}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2013}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 2.0, "year": 2013}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2013}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2013}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2013}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2013}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2013}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2013}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2013}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2013}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2013}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2013}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2013}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2013}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2013}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 4.0, "year": 2013}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2013}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2013}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2013}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2013}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 2.0, "year": 2013}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2013}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2013}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2013}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2013}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2013}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2013}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2013}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2013}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 4.0, "year": 2013}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2013}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2013}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2013}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2013}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2013}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2013}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 1.0, "year": 2013}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2013}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2013}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2013}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2013}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2013}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2013}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2013}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2013}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 1.0, "year": 2013}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2013}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2013}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2013}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2013}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2013}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2013}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2013}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2013}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 2.0, "year": 2013}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2013}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2013}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 2.0, "year": 2013}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 7.0, "year": 2013}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2013}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 3.0, "year": 2013}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2013}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 2.0, "year": 2013}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2013}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2013}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2013}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2013}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2013}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2013}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2013}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 3.0, "year": 2013}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2013}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2013}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2013}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 2.0, "year": 2013}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2013}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2013}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2013}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 3.0, "year": 2013}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 2.0, "year": 2013}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2013}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2013}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 7.0, "year": 2013}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2013}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2013}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 2.0, "year": 2013}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 7.0, "year": 2013}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2013}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 1.0, "year": 2013}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 1.0, "year": 2013}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2013}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 7.0, "year": 2013}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 1.0, "year": 2013}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 3.0, "year": 2013}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 9.0, "year": 2013}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2013}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2013}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 9.0, "year": 2013}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 3.0, "year": 2013}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2013}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2013}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 11.0, "year": 2013}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 8.0, "year": 2013}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 1.0, "year": 2013}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2013}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 13.0, "year": 2013}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 5.0, "year": 2013}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2013}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2013}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 3.0, "year": 2013}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 13.0, "year": 2013}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2013}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2013}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 6.0, "year": 2013}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2013}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2013}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 8.0, "year": 2013}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 9.0, "year": 2013}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 4.0, "year": 2013}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 10.0, "year": 2013}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 3.0, "year": 2013}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2013}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2013}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2013}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2013}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2013}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2013}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2013}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 2.0, "year": 2013}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2013}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 5.0, "year": 2013}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 3.0, "year": 2013}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2013}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2013}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 4.0, "year": 2013}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 7.0, "year": 2013}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 2.0, "year": 2013}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2013}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2013}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2013}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2013}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2013}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2013}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2013}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 5.0, "year": 2013}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2013}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2013}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2013}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2013}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 1.0, "year": 2013}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2013}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2013}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2013}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2013}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2013}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 5.0, "year": 2013}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2013}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 2.0, "year": 2013}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2013}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 5.0, "year": 2013}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2013}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2013}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2013}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2013}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 5.0, "year": 2013}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2013}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2013}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 4.0, "year": 2013}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 3.0, "year": 2013}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2013}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2013}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2013}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 4.0, "year": 2013}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2013}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2013}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2013}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2013}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2013}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2013}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2013}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2013}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2013}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 3.0, "year": 2013}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2013}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 2.0, "year": 2013}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2013}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 3.0, "year": 2013}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2013}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 4.0, "year": 2013}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2013}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 2.0, "year": 2013}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2013}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2013}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2013}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 3.0, "year": 2013}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2013}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2013}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2013}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2013}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2013}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 4.0, "year": 2013}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 2.0, "year": 2013}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2013}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 2.0, "year": 2013}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2013}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2013}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 1.0, "year": 2013}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 4.0, "year": 2013}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 3.0, "year": 2013}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2013}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2013}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 2.0, "year": 2013}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2013}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2013}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2013}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2013}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2013}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2013}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2013}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2013}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2013}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2013}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2013}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2013}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2013}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 3.0, "year": 2013}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2013}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2013}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 4.0, "year": 2013}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2013}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2013}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2013}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 2.0, "year": 2013}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2013}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 2.0, "year": 2013}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2013}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 1.0, "year": 2013}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2013}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 2.0, "year": 2013}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2013}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2013}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2013}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2013}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 1.0, "year": 2013}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2013}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2013}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2013}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2013}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2013}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 4.0, "year": 2013}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2013}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2013}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2013}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2013}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2013}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 1.0, "year": 2013}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 1.0, "year": 2013}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 2.0, "year": 2013}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2013}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2013}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2013}]}, {"2014": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2014}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2014}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2014}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 3.0, "year": 2014}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2014}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2014}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 11.0, "year": 2014}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2014}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2014}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 1.0, "year": 2014}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 6.0, "year": 2014}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2014}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2014}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2014}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 2.0, "year": 2014}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2014}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 6.0, "year": 2014}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 3.0, "year": 2014}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2014}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 7.0, "year": 2014}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 2.0, "year": 2014}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 2.0, "year": 2014}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 5.0, "year": 2014}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2014}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 6.0, "year": 2014}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 4.0, "year": 2014}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2014}, {"source": "1", "target": "33", "source_name": "critical temperature", "target_name": "strontium titanate", "weight": 1.0, "year": 2014}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 4.0, "year": 2014}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 1.0, "year": 2014}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 6.0, "year": 2014}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2014}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 18.0, "year": 2014}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 3.0, "year": 2014}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2014}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2014}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 2.0, "year": 2014}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 7.0, "year": 2014}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 7.0, "year": 2014}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 2.0, "year": 2014}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 9.0, "year": 2014}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2014}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 14.0, "year": 2014}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2014}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2014}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2014}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 4.0, "year": 2014}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 7.0, "year": 2014}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2014}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 2.0, "year": 2014}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 4.0, "year": 2014}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2014}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2014}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2014}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2014}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 10.0, "year": 2014}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2014}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 3.0, "year": 2014}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2014}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2014}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 6.0, "year": 2014}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2014}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2014}, {"source": "2", "target": "15", "source_name": "current density", "target_name": "magnetic flux", "weight": 1.0, "year": 2014}, {"source": "2", "target": "17", "source_name": "current density", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2014}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2014}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 1.0, "year": 2014}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2014}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2014}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2014}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2014}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2014}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 1.0, "year": 2014}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 28.0, "year": 2014}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 4.0, "year": 2014}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2014}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "2", "target": "45", "source_name": "current density", "target_name": "power transmission", "weight": 1.0, "year": 2014}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 5.0, "year": 2014}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 2.0, "year": 2014}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 3.0, "year": 2014}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 1.0, "year": 2014}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2014}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 2.0, "year": 2014}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 3.0, "year": 2014}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2014}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2014}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 2.0, "year": 2014}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 8.0, "year": 2014}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2014}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 5.0, "year": 2014}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2014}, {"source": "2", "target": "79", "source_name": "current density", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2014}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 4.0, "year": 2014}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2014}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2014}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2014}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2014}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2014}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2014}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2014}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 1.0, "year": 2014}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 3.0, "year": 2014}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2014}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2014}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2014}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2014}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2014}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2014}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2014}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 4.0, "year": 2014}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2014}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2014}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 2.0, "year": 2014}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 3.0, "year": 2014}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2014}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2014}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2014}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2014}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2014}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 3.0, "year": 2014}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2014}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2014}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 2.0, "year": 2014}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2014}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2014}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2014}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2014}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 2.0, "year": 2014}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2014}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2014}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 17.0, "year": 2014}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2014}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2014}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2014}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2014}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2014}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2014}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2014}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2014}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2014}, {"source": "10", "target": "13", "source_name": "liquid nitrogen", "target_name": "josephson junctions", "weight": 1.0, "year": 2014}, {"source": "10", "target": "14", "source_name": "liquid nitrogen", "target_name": "iron selenide", "weight": 1.0, "year": 2014}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2014}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 2.0, "year": 2014}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2014}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2014}, {"source": "10", "target": "22", "source_name": "liquid nitrogen", "target_name": "unit cell", "weight": 1.0, "year": 2014}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2014}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2014}, {"source": "10", "target": "33", "source_name": "liquid nitrogen", "target_name": "strontium titanate", "weight": 1.0, "year": 2014}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 2.0, "year": 2014}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 18.0, "year": 2014}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2014}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2014}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2014}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2014}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2014}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 3.0, "year": 2014}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2014}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2014}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2014}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2014}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2014}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2014}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 2.0, "year": 2014}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 3.0, "year": 2014}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2014}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2014}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2014}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 3.0, "year": 2014}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2014}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 5.0, "year": 2014}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2014}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2014}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 2.0, "year": 2014}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2014}, {"source": "11", "target": "51", "source_name": "yttrium barium copper oxide", "target_name": "wind turbine", "weight": 1.0, "year": 2014}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 7.0, "year": 2014}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2014}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2014}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2014}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 1.0, "year": 2014}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2014}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2014}, {"source": "12", "target": "60", "source_name": "scanning tunneling microscopy", "target_name": "mott insulator", "weight": 1.0, "year": 2014}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2014}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2014}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2014}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 3.0, "year": 2014}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2014}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2014}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 2.0, "year": 2014}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2014}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2014}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2014}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2014}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "14", "target": "22", "source_name": "iron selenide", "target_name": "unit cell", "weight": 1.0, "year": 2014}, {"source": "14", "target": "33", "source_name": "iron selenide", "target_name": "strontium titanate", "weight": 2.0, "year": 2014}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2014}, {"source": "15", "target": "20", "source_name": "magnetic flux", "target_name": "specific heat", "weight": 1.0, "year": 2014}, {"source": "15", "target": "23", "source_name": "magnetic flux", "target_name": "order parameter", "weight": 1.0, "year": 2014}, {"source": "15", "target": "32", "source_name": "magnetic flux", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2014}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2014}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 9.0, "year": 2014}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 1.0, "year": 2014}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 2.0, "year": 2014}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 2.0, "year": 2014}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2014}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "15", "target": "83", "source_name": "magnetic flux", "target_name": "permanent magnet", "weight": 1.0, "year": 2014}, {"source": "15", "target": "88", "source_name": "magnetic flux", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 2.0, "year": 2014}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2014}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2014}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2014}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 3.0, "year": 2014}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 2.0, "year": 2014}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2014}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2014}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2014}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2014}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2014}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 1.0, "year": 2014}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 1.0, "year": 2014}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2014}, {"source": "17", "target": "54", "source_name": "molecular beam epitaxy", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "17", "target": "70", "source_name": "molecular beam epitaxy", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 1.0, "year": 2014}, {"source": "17", "target": "90", "source_name": "molecular beam epitaxy", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 2.0, "year": 2014}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2014}, {"source": "18", "target": "30", "source_name": "fermi arcs", "target_name": "fermi level", "weight": 1.0, "year": 2014}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 2.0, "year": 2014}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2014}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 2.0, "year": 2014}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2014}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2014}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 4.0, "year": 2014}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 3.0, "year": 2014}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 3.0, "year": 2014}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 6.0, "year": 2014}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 3.0, "year": 2014}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 6.0, "year": 2014}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2014}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2014}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2014}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2014}, {"source": "20", "target": "54", "source_name": "specific heat", "target_name": "coherence length", "weight": 2.0, "year": 2014}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2014}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 8.0, "year": 2014}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 2.0, "year": 2014}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2014}, {"source": "20", "target": "79", "source_name": "specific heat", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2014}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 2.0, "year": 2014}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 3.0, "year": 2014}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 2.0, "year": 2014}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2014}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 2.0, "year": 2014}, {"source": "22", "target": "33", "source_name": "unit cell", "target_name": "strontium titanate", "weight": 1.0, "year": 2014}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 1.0, "year": 2014}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "23", "target": "26", "source_name": "order parameter", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2014}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2014}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2014}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2014}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2014}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2014}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2014}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 3.0, "year": 2014}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2014}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2014}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 2.0, "year": 2014}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2014}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2014}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2014}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2014}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2014}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2014}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2014}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2014}, {"source": "23", "target": "73", "source_name": "order parameter", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2014}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2014}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 6.0, "year": 2014}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 3.0, "year": 2014}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2014}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2014}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "24", "target": "64", "source_name": "magnetic resonance imaging", "target_name": "liquid helium", "weight": 1.0, "year": 2014}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2014}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2014}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 2.0, "year": 2014}, {"source": "24", "target": "88", "source_name": "magnetic resonance imaging", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2014}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 2.0, "year": 2014}, {"source": "26", "target": "90", "source_name": "carbon nanotubes", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2014}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2014}, {"source": "27", "target": "45", "source_name": "ac losses", "target_name": "power transmission", "weight": 1.0, "year": 2014}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2014}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2014}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2014}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2014}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2014}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2014}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 4.0, "year": 2014}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2014}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2014}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2014}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2014}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2014}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2014}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 1.0, "year": 2014}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2014}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2014}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2014}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2014}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2014}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2014}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2014}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2014}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2014}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 3.0, "year": 2014}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2014}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "30", "target": "54", "source_name": "fermi level", "target_name": "coherence length", "weight": 2.0, "year": 2014}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2014}, {"source": "30", "target": "58", "source_name": "fermi level", "target_name": "single crystal", "weight": 2.0, "year": 2014}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2014}, {"source": "30", "target": "72", "source_name": "fermi level", "target_name": "electrical resistance", "weight": 1.0, "year": 2014}, {"source": "30", "target": "79", "source_name": "fermi level", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "30", "target": "91", "source_name": "fermi level", "target_name": "heat capacity", "weight": 2.0, "year": 2014}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2014}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2014}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2014}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2014}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2014}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2014}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 2.0, "year": 2014}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2014}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2014}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2014}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 3.0, "year": 2014}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 8.0, "year": 2014}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2014}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 3.0, "year": 2014}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2014}, {"source": "34", "target": "49", "source_name": "exchange interaction", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 3.0, "year": 2014}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2014}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2014}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2014}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2014}, {"source": "36", "target": "54", "source_name": "ion beam", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2014}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2014}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2014}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 3.0, "year": 2014}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2014}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2014}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2014}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 4.0, "year": 2014}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2014}, {"source": "37", "target": "58", "source_name": "fermi surface", "target_name": "single crystal", "weight": 2.0, "year": 2014}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2014}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2014}, {"source": "37", "target": "68", "source_name": "fermi surface", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2014}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 3.0, "year": 2014}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 6.0, "year": 2014}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2014}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2014}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 7.0, "year": 2014}, {"source": "37", "target": "91", "source_name": "fermi surface", "target_name": "heat capacity", "weight": 2.0, "year": 2014}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2014}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2014}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 2.0, "year": 2014}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 7.0, "year": 2014}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2014}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 1.0, "year": 2014}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 1.0, "year": 2014}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2014}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 8.0, "year": 2014}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 2.0, "year": 2014}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 3.0, "year": 2014}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 3.0, "year": 2014}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 9.0, "year": 2014}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2014}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2014}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 10.0, "year": 2014}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 3.0, "year": 2014}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2014}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2014}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 11.0, "year": 2014}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 9.0, "year": 2014}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 1.0, "year": 2014}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2014}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 14.0, "year": 2014}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 6.0, "year": 2014}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2014}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2014}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 3.0, "year": 2014}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 14.0, "year": 2014}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2014}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2014}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 7.0, "year": 2014}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2014}, {"source": "40", "target": "79", "source_name": "magnetic field", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 2.0, "year": 2014}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 8.0, "year": 2014}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 9.0, "year": 2014}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 4.0, "year": 2014}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 11.0, "year": 2014}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 3.0, "year": 2014}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2014}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2014}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2014}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 2.0, "year": 2014}, {"source": "41", "target": "79", "source_name": "grain boundaries", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2014}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2014}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2014}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2014}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2014}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 3.0, "year": 2014}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2014}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 5.0, "year": 2014}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 4.0, "year": 2014}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2014}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2014}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 4.0, "year": 2014}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 7.0, "year": 2014}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 2.0, "year": 2014}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2014}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2014}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2014}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2014}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2014}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2014}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2014}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2014}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 5.0, "year": 2014}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2014}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2014}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2014}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2014}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 1.0, "year": 2014}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2014}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2014}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2014}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2014}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2014}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 5.0, "year": 2014}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2014}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 2.0, "year": 2014}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 5.0, "year": 2014}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2014}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2014}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2014}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2014}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 5.0, "year": 2014}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2014}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2014}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 4.0, "year": 2014}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 3.0, "year": 2014}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2014}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2014}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2014}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 4.0, "year": 2014}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2014}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2014}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2014}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2014}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2014}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2014}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2014}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2014}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 2.0, "year": 2014}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2014}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2014}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 3.0, "year": 2014}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2014}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 2.0, "year": 2014}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2014}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 3.0, "year": 2014}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2014}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 6.0, "year": 2014}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2014}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 2.0, "year": 2014}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2014}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 2.0, "year": 2014}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2014}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2014}, {"source": "54", "target": "79", "source_name": "coherence length", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 5.0, "year": 2014}, {"source": "54", "target": "91", "source_name": "coherence length", "target_name": "heat capacity", "weight": 2.0, "year": 2014}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2014}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2014}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2014}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2014}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 4.0, "year": 2014}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 2.0, "year": 2014}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2014}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 2.0, "year": 2014}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2014}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2014}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 1.0, "year": 2014}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 3.0, "year": 2014}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2014}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 4.0, "year": 2014}, {"source": "58", "target": "91", "source_name": "single crystal", "target_name": "heat capacity", "weight": 2.0, "year": 2014}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 3.0, "year": 2014}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2014}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2014}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "61", "target": "64", "source_name": "synchronous motor", "target_name": "liquid helium", "weight": 1.0, "year": 2014}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 2.0, "year": 2014}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2014}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2014}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2014}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2014}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2014}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2014}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2014}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2014}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2014}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2014}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2014}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2014}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2014}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 3.0, "year": 2014}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 3.0, "year": 2014}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2014}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2014}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 5.0, "year": 2014}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2014}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2014}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2014}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2014}, {"source": "68", "target": "79", "source_name": "nuclear magnetic resonance", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 2.0, "year": 2014}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2014}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 3.0, "year": 2014}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2014}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 1.0, "year": 2014}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2014}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2014}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2014}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2014}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2014}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 1.0, "year": 2014}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2014}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 3.0, "year": 2014}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2014}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2014}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2014}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2014}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 4.0, "year": 2014}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2014}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2014}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2014}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2014}, {"source": "79", "target": "91", "source_name": "crystal structure", "target_name": "heat capacity", "weight": 2.0, "year": 2014}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2014}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 2.0, "year": 2014}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 1.0, "year": 2014}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 3.0, "year": 2014}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2014}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2014}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2014}]}, {"2015": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2015}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2015}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2015}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 3.0, "year": 2015}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2015}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2015}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 12.0, "year": 2015}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2015}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2015}, {"source": "1", "target": "5", "source_name": "critical temperature", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2015}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 2.0, "year": 2015}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 7.0, "year": 2015}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2015}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2015}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2015}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 2.0, "year": 2015}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2015}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 10.0, "year": 2015}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 3.0, "year": 2015}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2015}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 7.0, "year": 2015}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 3.0, "year": 2015}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 3.0, "year": 2015}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 5.0, "year": 2015}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2015}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 9.0, "year": 2015}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 4.0, "year": 2015}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2015}, {"source": "1", "target": "33", "source_name": "critical temperature", "target_name": "strontium titanate", "weight": 1.0, "year": 2015}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 8.0, "year": 2015}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 1.0, "year": 2015}, {"source": "1", "target": "36", "source_name": "critical temperature", "target_name": "ion beam", "weight": 1.0, "year": 2015}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 6.0, "year": 2015}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2015}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 18.0, "year": 2015}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 4.0, "year": 2015}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2015}, {"source": "1", "target": "43", "source_name": "critical temperature", "target_name": "transmission electron microscopy", "weight": 4.0, "year": 2015}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 5.0, "year": 2015}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 3.0, "year": 2015}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 10.0, "year": 2015}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 7.0, "year": 2015}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 5.0, "year": 2015}, {"source": "1", "target": "57", "source_name": "critical temperature", "target_name": "density functional theory", "weight": 1.0, "year": 2015}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 9.0, "year": 2015}, {"source": "1", "target": "59", "source_name": "critical temperature", "target_name": "monte carlo", "weight": 3.0, "year": 2015}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2015}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 15.0, "year": 2015}, {"source": "1", "target": "66", "source_name": "critical temperature", "target_name": "sulfur hydride", "weight": 2.0, "year": 2015}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2015}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2015}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2015}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 7.0, "year": 2015}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 7.0, "year": 2015}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2015}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 4.0, "year": 2015}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 4.0, "year": 2015}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 3.0, "year": 2015}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2015}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2015}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2015}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2015}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 11.0, "year": 2015}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2015}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 4.0, "year": 2015}, {"source": "2", "target": "4", "source_name": "current density", "target_name": "penetration depth", "weight": 1.0, "year": 2015}, {"source": "2", "target": "5", "source_name": "current density", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2015}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2015}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2015}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 6.0, "year": 2015}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2015}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2015}, {"source": "2", "target": "14", "source_name": "current density", "target_name": "iron selenide", "weight": 1.0, "year": 2015}, {"source": "2", "target": "15", "source_name": "current density", "target_name": "magnetic flux", "weight": 1.0, "year": 2015}, {"source": "2", "target": "17", "source_name": "current density", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2015}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2015}, {"source": "2", "target": "20", "source_name": "current density", "target_name": "specific heat", "weight": 1.0, "year": 2015}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 2.0, "year": 2015}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2015}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2015}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2015}, {"source": "2", "target": "28", "source_name": "current density", "target_name": "bcs theory", "weight": 1.0, "year": 2015}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2015}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2015}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 2.0, "year": 2015}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 29.0, "year": 2015}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 4.0, "year": 2015}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2015}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "2", "target": "45", "source_name": "current density", "target_name": "power transmission", "weight": 1.0, "year": 2015}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 5.0, "year": 2015}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 2.0, "year": 2015}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 5.0, "year": 2015}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 3.0, "year": 2015}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 1.0, "year": 2015}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2015}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 2.0, "year": 2015}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 3.0, "year": 2015}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2015}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2015}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 2.0, "year": 2015}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 8.0, "year": 2015}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2015}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 5.0, "year": 2015}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2015}, {"source": "2", "target": "79", "source_name": "current density", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2015}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 4.0, "year": 2015}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2015}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2015}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2015}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2015}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2015}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "4", "target": "14", "source_name": "penetration depth", "target_name": "iron selenide", "weight": 1.0, "year": 2015}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2015}, {"source": "4", "target": "20", "source_name": "penetration depth", "target_name": "specific heat", "weight": 1.0, "year": 2015}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2015}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 2.0, "year": 2015}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 4.0, "year": 2015}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2015}, {"source": "4", "target": "55", "source_name": "penetration depth", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 2.0, "year": 2015}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2015}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "5", "target": "36", "source_name": "chemical vapor deposition", "target_name": "ion beam", "weight": 1.0, "year": 2015}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2015}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2015}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2015}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2015}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2015}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 4.0, "year": 2015}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2015}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2015}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 2.0, "year": 2015}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 4.0, "year": 2015}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2015}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2015}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2015}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2015}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2015}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 4.0, "year": 2015}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2015}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2015}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 3.0, "year": 2015}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2015}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2015}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2015}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2015}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 2.0, "year": 2015}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2015}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2015}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 17.0, "year": 2015}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2015}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2015}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2015}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2015}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2015}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2015}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2015}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2015}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2015}, {"source": "10", "target": "13", "source_name": "liquid nitrogen", "target_name": "josephson junctions", "weight": 1.0, "year": 2015}, {"source": "10", "target": "14", "source_name": "liquid nitrogen", "target_name": "iron selenide", "weight": 1.0, "year": 2015}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2015}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 2.0, "year": 2015}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2015}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2015}, {"source": "10", "target": "22", "source_name": "liquid nitrogen", "target_name": "unit cell", "weight": 1.0, "year": 2015}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2015}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2015}, {"source": "10", "target": "33", "source_name": "liquid nitrogen", "target_name": "strontium titanate", "weight": 1.0, "year": 2015}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 2.0, "year": 2015}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 18.0, "year": 2015}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2015}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2015}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2015}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2015}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2015}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 3.0, "year": 2015}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2015}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2015}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2015}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2015}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2015}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2015}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 2.0, "year": 2015}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 3.0, "year": 2015}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2015}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2015}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2015}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 3.0, "year": 2015}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2015}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 5.0, "year": 2015}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2015}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2015}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 2.0, "year": 2015}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2015}, {"source": "11", "target": "51", "source_name": "yttrium barium copper oxide", "target_name": "wind turbine", "weight": 1.0, "year": 2015}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 7.0, "year": 2015}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2015}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2015}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2015}, {"source": "12", "target": "22", "source_name": "scanning tunneling microscopy", "target_name": "unit cell", "weight": 3.0, "year": 2015}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 4.0, "year": 2015}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2015}, {"source": "12", "target": "58", "source_name": "scanning tunneling microscopy", "target_name": "single crystal", "weight": 3.0, "year": 2015}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2015}, {"source": "12", "target": "60", "source_name": "scanning tunneling microscopy", "target_name": "mott insulator", "weight": 1.0, "year": 2015}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2015}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2015}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2015}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 3.0, "year": 2015}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2015}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2015}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 2.0, "year": 2015}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2015}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2015}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2015}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2015}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "14", "target": "20", "source_name": "iron selenide", "target_name": "specific heat", "weight": 1.0, "year": 2015}, {"source": "14", "target": "22", "source_name": "iron selenide", "target_name": "unit cell", "weight": 1.0, "year": 2015}, {"source": "14", "target": "28", "source_name": "iron selenide", "target_name": "bcs theory", "weight": 1.0, "year": 2015}, {"source": "14", "target": "33", "source_name": "iron selenide", "target_name": "strontium titanate", "weight": 2.0, "year": 2015}, {"source": "14", "target": "40", "source_name": "iron selenide", "target_name": "magnetic field", "weight": 1.0, "year": 2015}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 2.0, "year": 2015}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2015}, {"source": "15", "target": "20", "source_name": "magnetic flux", "target_name": "specific heat", "weight": 1.0, "year": 2015}, {"source": "15", "target": "23", "source_name": "magnetic flux", "target_name": "order parameter", "weight": 1.0, "year": 2015}, {"source": "15", "target": "32", "source_name": "magnetic flux", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2015}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2015}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 9.0, "year": 2015}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 1.0, "year": 2015}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 2.0, "year": 2015}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 2.0, "year": 2015}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2015}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "15", "target": "83", "source_name": "magnetic flux", "target_name": "permanent magnet", "weight": 1.0, "year": 2015}, {"source": "15", "target": "88", "source_name": "magnetic flux", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 2.0, "year": 2015}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2015}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2015}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2015}, {"source": "16", "target": "34", "source_name": "coulomb repulsion", "target_name": "exchange interaction", "weight": 4.0, "year": 2015}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 7.0, "year": 2015}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 6.0, "year": 2015}, {"source": "16", "target": "59", "source_name": "coulomb repulsion", "target_name": "monte carlo", "weight": 3.0, "year": 2015}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2015}, {"source": "16", "target": "72", "source_name": "coulomb repulsion", "target_name": "electrical resistance", "weight": 1.0, "year": 2015}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2015}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2015}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2015}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2015}, {"source": "17", "target": "19", "source_name": "molecular beam epitaxy", "target_name": "electric field", "weight": 1.0, "year": 2015}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 4.0, "year": 2015}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 5.0, "year": 2015}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2015}, {"source": "17", "target": "54", "source_name": "molecular beam epitaxy", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 4.0, "year": 2015}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "17", "target": "70", "source_name": "molecular beam epitaxy", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 2.0, "year": 2015}, {"source": "17", "target": "90", "source_name": "molecular beam epitaxy", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 2.0, "year": 2015}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2015}, {"source": "18", "target": "30", "source_name": "fermi arcs", "target_name": "fermi level", "weight": 1.0, "year": 2015}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 2.0, "year": 2015}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2015}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 2.0, "year": 2015}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2015}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2015}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 5.0, "year": 2015}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "19", "target": "87", "source_name": "electric field", "target_name": "charge transfer", "weight": 1.0, "year": 2015}, {"source": "20", "target": "22", "source_name": "specific heat", "target_name": "unit cell", "weight": 1.0, "year": 2015}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 3.0, "year": 2015}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 4.0, "year": 2015}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 6.0, "year": 2015}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 3.0, "year": 2015}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 7.0, "year": 2015}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2015}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2015}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2015}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2015}, {"source": "20", "target": "54", "source_name": "specific heat", "target_name": "coherence length", "weight": 2.0, "year": 2015}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2015}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 9.0, "year": 2015}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 2.0, "year": 2015}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2015}, {"source": "20", "target": "79", "source_name": "specific heat", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2015}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 2.0, "year": 2015}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 4.0, "year": 2015}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 3.0, "year": 2015}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2015}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "21", "target": "46", "source_name": "grain boundary", "target_name": "iron pnictides", "weight": 1.0, "year": 2015}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "22", "target": "28", "source_name": "unit cell", "target_name": "bcs theory", "weight": 1.0, "year": 2015}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 2.0, "year": 2015}, {"source": "22", "target": "33", "source_name": "unit cell", "target_name": "strontium titanate", "weight": 1.0, "year": 2015}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 4.0, "year": 2015}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "22", "target": "58", "source_name": "unit cell", "target_name": "single crystal", "weight": 3.0, "year": 2015}, {"source": "22", "target": "70", "source_name": "unit cell", "target_name": "meissner effect", "weight": 2.0, "year": 2015}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "23", "target": "26", "source_name": "order parameter", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2015}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2015}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2015}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2015}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2015}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2015}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 2.0, "year": 2015}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 3.0, "year": 2015}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2015}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2015}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 3.0, "year": 2015}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2015}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2015}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2015}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2015}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2015}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2015}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2015}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2015}, {"source": "23", "target": "73", "source_name": "order parameter", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2015}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2015}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 6.0, "year": 2015}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 3.0, "year": 2015}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2015}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2015}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "24", "target": "64", "source_name": "magnetic resonance imaging", "target_name": "liquid helium", "weight": 1.0, "year": 2015}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2015}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2015}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 2.0, "year": 2015}, {"source": "24", "target": "88", "source_name": "magnetic resonance imaging", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2015}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 2.0, "year": 2015}, {"source": "26", "target": "90", "source_name": "carbon nanotubes", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2015}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2015}, {"source": "27", "target": "45", "source_name": "ac losses", "target_name": "power transmission", "weight": 1.0, "year": 2015}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2015}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2015}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2015}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2015}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2015}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2015}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 5.0, "year": 2015}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2015}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2015}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2015}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2015}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2015}, {"source": "28", "target": "58", "source_name": "bcs theory", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2015}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 1.0, "year": 2015}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2015}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2015}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2015}, {"source": "28", "target": "79", "source_name": "bcs theory", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2015}, {"source": "28", "target": "92", "source_name": "bcs theory", "target_name": "ab initio", "weight": 1.0, "year": 2015}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2015}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2015}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2015}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2015}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2015}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 3.0, "year": 2015}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2015}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "30", "target": "54", "source_name": "fermi level", "target_name": "coherence length", "weight": 2.0, "year": 2015}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2015}, {"source": "30", "target": "58", "source_name": "fermi level", "target_name": "single crystal", "weight": 2.0, "year": 2015}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2015}, {"source": "30", "target": "72", "source_name": "fermi level", "target_name": "electrical resistance", "weight": 1.0, "year": 2015}, {"source": "30", "target": "79", "source_name": "fermi level", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "30", "target": "91", "source_name": "fermi level", "target_name": "heat capacity", "weight": 2.0, "year": 2015}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2015}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2015}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2015}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2015}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2015}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2015}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 2.0, "year": 2015}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2015}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2015}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2015}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 3.0, "year": 2015}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 8.0, "year": 2015}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2015}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 3.0, "year": 2015}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2015}, {"source": "34", "target": "49", "source_name": "exchange interaction", "target_name": "strongly correlated", "weight": 4.0, "year": 2015}, {"source": "34", "target": "56", "source_name": "exchange interaction", "target_name": "hubbard model", "weight": 3.0, "year": 2015}, {"source": "34", "target": "59", "source_name": "exchange interaction", "target_name": "monte carlo", "weight": 3.0, "year": 2015}, {"source": "34", "target": "72", "source_name": "exchange interaction", "target_name": "electrical resistance", "weight": 1.0, "year": 2015}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 3.0, "year": 2015}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2015}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2015}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2015}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2015}, {"source": "36", "target": "54", "source_name": "ion beam", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2015}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2015}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2015}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 3.0, "year": 2015}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2015}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2015}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2015}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 4.0, "year": 2015}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2015}, {"source": "37", "target": "58", "source_name": "fermi surface", "target_name": "single crystal", "weight": 2.0, "year": 2015}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2015}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2015}, {"source": "37", "target": "68", "source_name": "fermi surface", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2015}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 5.0, "year": 2015}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 6.0, "year": 2015}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2015}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2015}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 7.0, "year": 2015}, {"source": "37", "target": "91", "source_name": "fermi surface", "target_name": "heat capacity", "weight": 2.0, "year": 2015}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2015}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2015}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 2.0, "year": 2015}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 7.0, "year": 2015}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2015}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 1.0, "year": 2015}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 1.0, "year": 2015}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2015}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 9.0, "year": 2015}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 2.0, "year": 2015}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 3.0, "year": 2015}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 3.0, "year": 2015}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 9.0, "year": 2015}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2015}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2015}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 10.0, "year": 2015}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 3.0, "year": 2015}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2015}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2015}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 15.0, "year": 2015}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 9.0, "year": 2015}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 1.0, "year": 2015}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2015}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 14.0, "year": 2015}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 6.0, "year": 2015}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2015}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2015}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 3.0, "year": 2015}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 14.0, "year": 2015}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2015}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2015}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 7.0, "year": 2015}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2015}, {"source": "40", "target": "79", "source_name": "magnetic field", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 3.0, "year": 2015}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 8.0, "year": 2015}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 9.0, "year": 2015}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 4.0, "year": 2015}, {"source": "40", "target": "87", "source_name": "magnetic field", "target_name": "charge transfer", "weight": 1.0, "year": 2015}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 12.0, "year": 2015}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 3.0, "year": 2015}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2015}, {"source": "41", "target": "46", "source_name": "grain boundaries", "target_name": "iron pnictides", "weight": 1.0, "year": 2015}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2015}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2015}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 2.0, "year": 2015}, {"source": "41", "target": "79", "source_name": "grain boundaries", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2015}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2015}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2015}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2015}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "43", "target": "68", "source_name": "transmission electron microscopy", "target_name": "nuclear magnetic resonance", "weight": 4.0, "year": 2015}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2015}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 3.0, "year": 2015}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2015}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 5.0, "year": 2015}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 4.0, "year": 2015}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2015}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2015}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 4.0, "year": 2015}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 7.0, "year": 2015}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 2.0, "year": 2015}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2015}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2015}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2015}, {"source": "44", "target": "66", "source_name": "phase diagram", "target_name": "sulfur hydride", "weight": 3.0, "year": 2015}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2015}, {"source": "44", "target": "69", "source_name": "phase diagram", "target_name": "selenium hydrides", "weight": 3.0, "year": 2015}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2015}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2015}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2015}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2015}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 5.0, "year": 2015}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2015}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2015}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2015}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2015}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 1.0, "year": 2015}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2015}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2015}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2015}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2015}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2015}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 5.0, "year": 2015}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2015}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 2.0, "year": 2015}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "47", "target": "91", "source_name": "magnetic susceptibility", "target_name": "heat capacity", "weight": 1.0, "year": 2015}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 5.0, "year": 2015}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2015}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2015}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2015}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2015}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 5.0, "year": 2015}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2015}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2015}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 8.0, "year": 2015}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 6.0, "year": 2015}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2015}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2015}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2015}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 4.0, "year": 2015}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2015}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2015}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2015}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2015}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2015}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2015}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2015}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2015}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 2.0, "year": 2015}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2015}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2015}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 3.0, "year": 2015}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2015}, {"source": "53", "target": "55", "source_name": "spectral weight", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 2.0, "year": 2015}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2015}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 3.0, "year": 2015}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2015}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 6.0, "year": 2015}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2015}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 2.0, "year": 2015}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2015}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 2.0, "year": 2015}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2015}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2015}, {"source": "54", "target": "79", "source_name": "coherence length", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 5.0, "year": 2015}, {"source": "54", "target": "91", "source_name": "coherence length", "target_name": "heat capacity", "weight": 2.0, "year": 2015}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2015}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2015}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2015}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2015}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 7.0, "year": 2015}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 2.0, "year": 2015}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2015}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 2.0, "year": 2015}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2015}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2015}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 1.0, "year": 2015}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 3.0, "year": 2015}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2015}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 4.0, "year": 2015}, {"source": "58", "target": "91", "source_name": "single crystal", "target_name": "heat capacity", "weight": 2.0, "year": 2015}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 3.0, "year": 2015}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2015}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2015}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "61", "target": "64", "source_name": "synchronous motor", "target_name": "liquid helium", "weight": 1.0, "year": 2015}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 2.0, "year": 2015}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2015}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2015}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2015}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2015}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2015}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2015}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2015}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2015}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2015}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2015}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2015}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2015}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2015}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 3.0, "year": 2015}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 3.0, "year": 2015}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2015}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2015}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 5.0, "year": 2015}, {"source": "66", "target": "69", "source_name": "sulfur hydride", "target_name": "selenium hydrides", "weight": 3.0, "year": 2015}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2015}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2015}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2015}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2015}, {"source": "68", "target": "79", "source_name": "nuclear magnetic resonance", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 2.0, "year": 2015}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2015}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 3.0, "year": 2015}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2015}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 3.0, "year": 2015}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2015}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2015}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2015}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2015}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2015}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 1.0, "year": 2015}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2015}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 3.0, "year": 2015}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2015}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2015}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2015}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2015}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 4.0, "year": 2015}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2015}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2015}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2015}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "79", "target": "84", "source_name": "crystal structure", "target_name": "ground state", "weight": 2.0, "year": 2015}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2015}, {"source": "79", "target": "91", "source_name": "crystal structure", "target_name": "heat capacity", "weight": 2.0, "year": 2015}, {"source": "79", "target": "92", "source_name": "crystal structure", "target_name": "ab initio", "weight": 1.0, "year": 2015}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2015}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 2.0, "year": 2015}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 1.0, "year": 2015}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 3.0, "year": 2015}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2015}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2015}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2015}]}, {"2016": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2016}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2016}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2016}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2016}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 3.0, "year": 2016}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2016}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2016}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 18.0, "year": 2016}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2016}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 2.0, "year": 2016}, {"source": "1", "target": "5", "source_name": "critical temperature", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2016}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 2.0, "year": 2016}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 8.0, "year": 2016}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2016}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2016}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2016}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 2.0, "year": 2016}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2016}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 10.0, "year": 2016}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2016}, {"source": "1", "target": "18", "source_name": "critical temperature", "target_name": "fermi arcs", "weight": 5.0, "year": 2016}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 2.0, "year": 2016}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 12.0, "year": 2016}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 4.0, "year": 2016}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 3.0, "year": 2016}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 6.0, "year": 2016}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2016}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 11.0, "year": 2016}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 4.0, "year": 2016}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2016}, {"source": "1", "target": "33", "source_name": "critical temperature", "target_name": "strontium titanate", "weight": 2.0, "year": 2016}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 10.0, "year": 2016}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 1.0, "year": 2016}, {"source": "1", "target": "36", "source_name": "critical temperature", "target_name": "ion beam", "weight": 1.0, "year": 2016}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 8.0, "year": 2016}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2016}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 24.0, "year": 2016}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 4.0, "year": 2016}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2016}, {"source": "1", "target": "43", "source_name": "critical temperature", "target_name": "transmission electron microscopy", "weight": 5.0, "year": 2016}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 8.0, "year": 2016}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 3.0, "year": 2016}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2016}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 10.0, "year": 2016}, {"source": "1", "target": "52", "source_name": "critical temperature", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2016}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 7.0, "year": 2016}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 5.0, "year": 2016}, {"source": "1", "target": "57", "source_name": "critical temperature", "target_name": "density functional theory", "weight": 3.0, "year": 2016}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 11.0, "year": 2016}, {"source": "1", "target": "59", "source_name": "critical temperature", "target_name": "monte carlo", "weight": 3.0, "year": 2016}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2016}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 21.0, "year": 2016}, {"source": "1", "target": "66", "source_name": "critical temperature", "target_name": "sulfur hydride", "weight": 5.0, "year": 2016}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2016}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 6.0, "year": 2016}, {"source": "1", "target": "69", "source_name": "critical temperature", "target_name": "selenium hydrides", "weight": 2.0, "year": 2016}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2016}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 7.0, "year": 2016}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 8.0, "year": 2016}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2016}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 4.0, "year": 2016}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 4.0, "year": 2016}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 3.0, "year": 2016}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2016}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2016}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2016}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2016}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 12.0, "year": 2016}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2016}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 4.0, "year": 2016}, {"source": "2", "target": "4", "source_name": "current density", "target_name": "penetration depth", "weight": 1.0, "year": 2016}, {"source": "2", "target": "5", "source_name": "current density", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2016}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2016}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2016}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 6.0, "year": 2016}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2016}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2016}, {"source": "2", "target": "14", "source_name": "current density", "target_name": "iron selenide", "weight": 1.0, "year": 2016}, {"source": "2", "target": "15", "source_name": "current density", "target_name": "magnetic flux", "weight": 1.0, "year": 2016}, {"source": "2", "target": "17", "source_name": "current density", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2016}, {"source": "2", "target": "18", "source_name": "current density", "target_name": "fermi arcs", "weight": 5.0, "year": 2016}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2016}, {"source": "2", "target": "20", "source_name": "current density", "target_name": "specific heat", "weight": 6.0, "year": 2016}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 3.0, "year": 2016}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2016}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2016}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2016}, {"source": "2", "target": "28", "source_name": "current density", "target_name": "bcs theory", "weight": 1.0, "year": 2016}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2016}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2016}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 2.0, "year": 2016}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2016}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 35.0, "year": 2016}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 4.0, "year": 2016}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2016}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "2", "target": "45", "source_name": "current density", "target_name": "power transmission", "weight": 1.0, "year": 2016}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 5.0, "year": 2016}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 2.0, "year": 2016}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 5.0, "year": 2016}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 3.0, "year": 2016}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 1.0, "year": 2016}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2016}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 2.0, "year": 2016}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 8.0, "year": 2016}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2016}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2016}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 2.0, "year": 2016}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 8.0, "year": 2016}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2016}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 6.0, "year": 2016}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2016}, {"source": "2", "target": "79", "source_name": "current density", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2016}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 4.0, "year": 2016}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2016}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 1.0, "year": 2016}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2016}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 1.0, "year": 2016}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2016}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2016}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "4", "target": "14", "source_name": "penetration depth", "target_name": "iron selenide", "weight": 1.0, "year": 2016}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2016}, {"source": "4", "target": "20", "source_name": "penetration depth", "target_name": "specific heat", "weight": 1.0, "year": 2016}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2016}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 2.0, "year": 2016}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 4.0, "year": 2016}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2016}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2016}, {"source": "4", "target": "55", "source_name": "penetration depth", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 2.0, "year": 2016}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2016}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "5", "target": "23", "source_name": "chemical vapor deposition", "target_name": "order parameter", "weight": 1.0, "year": 2016}, {"source": "5", "target": "36", "source_name": "chemical vapor deposition", "target_name": "ion beam", "weight": 1.0, "year": 2016}, {"source": "5", "target": "40", "source_name": "chemical vapor deposition", "target_name": "magnetic field", "weight": 1.0, "year": 2016}, {"source": "5", "target": "88", "source_name": "chemical vapor deposition", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2016}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2016}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2016}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 2.0, "year": 2016}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2016}, {"source": "6", "target": "34", "source_name": "brillouin zone", "target_name": "exchange interaction", "weight": 1.0, "year": 2016}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 5.0, "year": 2016}, {"source": "6", "target": "44", "source_name": "brillouin zone", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2016}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 2.0, "year": 2016}, {"source": "6", "target": "57", "source_name": "brillouin zone", "target_name": "density functional theory", "weight": 1.0, "year": 2016}, {"source": "6", "target": "79", "source_name": "brillouin zone", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 3.0, "year": 2016}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 4.0, "year": 2016}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2016}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2016}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2016}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2016}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2016}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 5.0, "year": 2016}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2016}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2016}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 4.0, "year": 2016}, {"source": "7", "target": "59", "source_name": "kinetic energy", "target_name": "monte carlo", "weight": 1.0, "year": 2016}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2016}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "8", "target": "22", "source_name": "symmetry breaking", "target_name": "unit cell", "weight": 1.0, "year": 2016}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2016}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2016}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 2.0, "year": 2016}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2016}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2016}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 17.0, "year": 2016}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 1.0, "year": 2016}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2016}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2016}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2016}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2016}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2016}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2016}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2016}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2016}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2016}, {"source": "10", "target": "13", "source_name": "liquid nitrogen", "target_name": "josephson junctions", "weight": 1.0, "year": 2016}, {"source": "10", "target": "14", "source_name": "liquid nitrogen", "target_name": "iron selenide", "weight": 1.0, "year": 2016}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2016}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 2.0, "year": 2016}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2016}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2016}, {"source": "10", "target": "22", "source_name": "liquid nitrogen", "target_name": "unit cell", "weight": 1.0, "year": 2016}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2016}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2016}, {"source": "10", "target": "33", "source_name": "liquid nitrogen", "target_name": "strontium titanate", "weight": 1.0, "year": 2016}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 2.0, "year": 2016}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2016}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 18.0, "year": 2016}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2016}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2016}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2016}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 4.0, "year": 2016}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2016}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2016}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 3.0, "year": 2016}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2016}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2016}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2016}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2016}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2016}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2016}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 2.0, "year": 2016}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 3.0, "year": 2016}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2016}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2016}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2016}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 3.0, "year": 2016}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2016}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 5.0, "year": 2016}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2016}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2016}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 2.0, "year": 2016}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2016}, {"source": "11", "target": "51", "source_name": "yttrium barium copper oxide", "target_name": "wind turbine", "weight": 1.0, "year": 2016}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 7.0, "year": 2016}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2016}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 6.0, "year": 2016}, {"source": "12", "target": "19", "source_name": "scanning tunneling microscopy", "target_name": "electric field", "weight": 2.0, "year": 2016}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2016}, {"source": "12", "target": "22", "source_name": "scanning tunneling microscopy", "target_name": "unit cell", "weight": 5.0, "year": 2016}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 6.0, "year": 2016}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2016}, {"source": "12", "target": "58", "source_name": "scanning tunneling microscopy", "target_name": "single crystal", "weight": 3.0, "year": 2016}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2016}, {"source": "12", "target": "60", "source_name": "scanning tunneling microscopy", "target_name": "mott insulator", "weight": 1.0, "year": 2016}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "12", "target": "87", "source_name": "scanning tunneling microscopy", "target_name": "charge transfer", "weight": 3.0, "year": 2016}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2016}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2016}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2016}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 3.0, "year": 2016}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2016}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2016}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 2.0, "year": 2016}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2016}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2016}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2016}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2016}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "14", "target": "20", "source_name": "iron selenide", "target_name": "specific heat", "weight": 1.0, "year": 2016}, {"source": "14", "target": "22", "source_name": "iron selenide", "target_name": "unit cell", "weight": 1.0, "year": 2016}, {"source": "14", "target": "28", "source_name": "iron selenide", "target_name": "bcs theory", "weight": 1.0, "year": 2016}, {"source": "14", "target": "33", "source_name": "iron selenide", "target_name": "strontium titanate", "weight": 3.0, "year": 2016}, {"source": "14", "target": "40", "source_name": "iron selenide", "target_name": "magnetic field", "weight": 1.0, "year": 2016}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2016}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 2.0, "year": 2016}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2016}, {"source": "15", "target": "20", "source_name": "magnetic flux", "target_name": "specific heat", "weight": 1.0, "year": 2016}, {"source": "15", "target": "23", "source_name": "magnetic flux", "target_name": "order parameter", "weight": 1.0, "year": 2016}, {"source": "15", "target": "32", "source_name": "magnetic flux", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2016}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2016}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 10.0, "year": 2016}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 1.0, "year": 2016}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 2.0, "year": 2016}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 3.0, "year": 2016}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2016}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "15", "target": "83", "source_name": "magnetic flux", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "15", "target": "88", "source_name": "magnetic flux", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 2.0, "year": 2016}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2016}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2016}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2016}, {"source": "16", "target": "34", "source_name": "coulomb repulsion", "target_name": "exchange interaction", "weight": 4.0, "year": 2016}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2016}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2016}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 7.0, "year": 2016}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 6.0, "year": 2016}, {"source": "16", "target": "59", "source_name": "coulomb repulsion", "target_name": "monte carlo", "weight": 3.0, "year": 2016}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2016}, {"source": "16", "target": "72", "source_name": "coulomb repulsion", "target_name": "electrical resistance", "weight": 1.0, "year": 2016}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2016}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2016}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2016}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2016}, {"source": "17", "target": "19", "source_name": "molecular beam epitaxy", "target_name": "electric field", "weight": 3.0, "year": 2016}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 5.0, "year": 2016}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 7.0, "year": 2016}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2016}, {"source": "17", "target": "54", "source_name": "molecular beam epitaxy", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 4.0, "year": 2016}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 2.0, "year": 2016}, {"source": "17", "target": "70", "source_name": "molecular beam epitaxy", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 2.0, "year": 2016}, {"source": "17", "target": "90", "source_name": "molecular beam epitaxy", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 7.0, "year": 2016}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2016}, {"source": "18", "target": "30", "source_name": "fermi arcs", "target_name": "fermi level", "weight": 1.0, "year": 2016}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2016}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 7.0, "year": 2016}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2016}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 7.0, "year": 2016}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2016}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2016}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 8.0, "year": 2016}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2016}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "19", "target": "87", "source_name": "electric field", "target_name": "charge transfer", "weight": 1.0, "year": 2016}, {"source": "20", "target": "22", "source_name": "specific heat", "target_name": "unit cell", "weight": 1.0, "year": 2016}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 3.0, "year": 2016}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 4.0, "year": 2016}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 6.0, "year": 2016}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 3.0, "year": 2016}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 12.0, "year": 2016}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2016}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2016}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2016}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2016}, {"source": "20", "target": "54", "source_name": "specific heat", "target_name": "coherence length", "weight": 2.0, "year": 2016}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2016}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 9.0, "year": 2016}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 7.0, "year": 2016}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2016}, {"source": "20", "target": "79", "source_name": "specific heat", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2016}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 2.0, "year": 2016}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 4.0, "year": 2016}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 3.0, "year": 2016}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2016}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "21", "target": "46", "source_name": "grain boundary", "target_name": "iron pnictides", "weight": 1.0, "year": 2016}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "22", "target": "28", "source_name": "unit cell", "target_name": "bcs theory", "weight": 1.0, "year": 2016}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 2.0, "year": 2016}, {"source": "22", "target": "33", "source_name": "unit cell", "target_name": "strontium titanate", "weight": 1.0, "year": 2016}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 4.0, "year": 2016}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "22", "target": "58", "source_name": "unit cell", "target_name": "single crystal", "weight": 3.0, "year": 2016}, {"source": "22", "target": "70", "source_name": "unit cell", "target_name": "meissner effect", "weight": 2.0, "year": 2016}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "22", "target": "87", "source_name": "unit cell", "target_name": "charge transfer", "weight": 2.0, "year": 2016}, {"source": "23", "target": "26", "source_name": "order parameter", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2016}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2016}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2016}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2016}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2016}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2016}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 4.0, "year": 2016}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 3.0, "year": 2016}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2016}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2016}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2016}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 3.0, "year": 2016}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2016}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2016}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2016}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2016}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2016}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2016}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2016}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2016}, {"source": "23", "target": "73", "source_name": "order parameter", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2016}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2016}, {"source": "23", "target": "88", "source_name": "order parameter", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 6.0, "year": 2016}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 3.0, "year": 2016}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2016}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2016}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "24", "target": "64", "source_name": "magnetic resonance imaging", "target_name": "liquid helium", "weight": 1.0, "year": 2016}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2016}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2016}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 2.0, "year": 2016}, {"source": "24", "target": "88", "source_name": "magnetic resonance imaging", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2016}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2016}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 2.0, "year": 2016}, {"source": "26", "target": "90", "source_name": "carbon nanotubes", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 2.0, "year": 2016}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2016}, {"source": "27", "target": "45", "source_name": "ac losses", "target_name": "power transmission", "weight": 1.0, "year": 2016}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2016}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2016}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2016}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2016}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2016}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 3.0, "year": 2016}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2016}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 5.0, "year": 2016}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2016}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2016}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2016}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2016}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2016}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2016}, {"source": "28", "target": "58", "source_name": "bcs theory", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2016}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 1.0, "year": 2016}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2016}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2016}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2016}, {"source": "28", "target": "79", "source_name": "bcs theory", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2016}, {"source": "28", "target": "92", "source_name": "bcs theory", "target_name": "ab initio", "weight": 1.0, "year": 2016}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2016}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2016}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2016}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2016}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2016}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 3.0, "year": 2016}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2016}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "30", "target": "54", "source_name": "fermi level", "target_name": "coherence length", "weight": 2.0, "year": 2016}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2016}, {"source": "30", "target": "58", "source_name": "fermi level", "target_name": "single crystal", "weight": 2.0, "year": 2016}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 1.0, "year": 2016}, {"source": "30", "target": "72", "source_name": "fermi level", "target_name": "electrical resistance", "weight": 1.0, "year": 2016}, {"source": "30", "target": "79", "source_name": "fermi level", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "30", "target": "91", "source_name": "fermi level", "target_name": "heat capacity", "weight": 2.0, "year": 2016}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2016}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2016}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2016}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2016}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "31", "target": "58", "source_name": "condensed matter", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2016}, {"source": "31", "target": "62", "source_name": "condensed matter", "target_name": "alternating current", "weight": 1.0, "year": 2016}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2016}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 3.0, "year": 2016}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2016}, {"source": "31", "target": "91", "source_name": "condensed matter", "target_name": "heat capacity", "weight": 1.0, "year": 2016}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2016}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2016}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 3.0, "year": 2016}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 8.0, "year": 2016}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2016}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 4.0, "year": 2016}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2016}, {"source": "34", "target": "49", "source_name": "exchange interaction", "target_name": "strongly correlated", "weight": 4.0, "year": 2016}, {"source": "34", "target": "56", "source_name": "exchange interaction", "target_name": "hubbard model", "weight": 3.0, "year": 2016}, {"source": "34", "target": "57", "source_name": "exchange interaction", "target_name": "density functional theory", "weight": 1.0, "year": 2016}, {"source": "34", "target": "59", "source_name": "exchange interaction", "target_name": "monte carlo", "weight": 3.0, "year": 2016}, {"source": "34", "target": "66", "source_name": "exchange interaction", "target_name": "sulfur hydride", "weight": 2.0, "year": 2016}, {"source": "34", "target": "72", "source_name": "exchange interaction", "target_name": "electrical resistance", "weight": 1.0, "year": 2016}, {"source": "34", "target": "79", "source_name": "exchange interaction", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 2.0, "year": 2016}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 3.0, "year": 2016}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2016}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2016}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2016}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2016}, {"source": "36", "target": "54", "source_name": "ion beam", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2016}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2016}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2016}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 3.0, "year": 2016}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2016}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2016}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2016}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 4.0, "year": 2016}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2016}, {"source": "37", "target": "57", "source_name": "fermi surface", "target_name": "density functional theory", "weight": 1.0, "year": 2016}, {"source": "37", "target": "58", "source_name": "fermi surface", "target_name": "single crystal", "weight": 2.0, "year": 2016}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2016}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2016}, {"source": "37", "target": "68", "source_name": "fermi surface", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2016}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 5.0, "year": 2016}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 8.0, "year": 2016}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2016}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2016}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 8.0, "year": 2016}, {"source": "37", "target": "91", "source_name": "fermi surface", "target_name": "heat capacity", "weight": 2.0, "year": 2016}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2016}, {"source": "38", "target": "66", "source_name": "metallic hydrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2016}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "38", "target": "79", "source_name": "metallic hydrogen", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2016}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 2.0, "year": 2016}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 7.0, "year": 2016}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2016}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 1.0, "year": 2016}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 2.0, "year": 2016}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2016}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 11.0, "year": 2016}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 2.0, "year": 2016}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 3.0, "year": 2016}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 3.0, "year": 2016}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 9.0, "year": 2016}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 5.0, "year": 2016}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2016}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 11.0, "year": 2016}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 3.0, "year": 2016}, {"source": "40", "target": "52", "source_name": "magnetic field", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2016}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2016}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2016}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 16.0, "year": 2016}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 9.0, "year": 2016}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 2.0, "year": 2016}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2016}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 15.0, "year": 2016}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 11.0, "year": 2016}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2016}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2016}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 3.0, "year": 2016}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 14.0, "year": 2016}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2016}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2016}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 9.0, "year": 2016}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 2.0, "year": 2016}, {"source": "40", "target": "79", "source_name": "magnetic field", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 3.0, "year": 2016}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 8.0, "year": 2016}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 10.0, "year": 2016}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 4.0, "year": 2016}, {"source": "40", "target": "87", "source_name": "magnetic field", "target_name": "charge transfer", "weight": 1.0, "year": 2016}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 13.0, "year": 2016}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 3.0, "year": 2016}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2016}, {"source": "41", "target": "46", "source_name": "grain boundaries", "target_name": "iron pnictides", "weight": 1.0, "year": 2016}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2016}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2016}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 2.0, "year": 2016}, {"source": "41", "target": "79", "source_name": "grain boundaries", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2016}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2016}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2016}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "43", "target": "68", "source_name": "transmission electron microscopy", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2016}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2016}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 4.0, "year": 2016}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2016}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 6.0, "year": 2016}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 4.0, "year": 2016}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2016}, {"source": "44", "target": "53", "source_name": "phase diagram", "target_name": "spectral weight", "weight": 1.0, "year": 2016}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2016}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 4.0, "year": 2016}, {"source": "44", "target": "57", "source_name": "phase diagram", "target_name": "density functional theory", "weight": 2.0, "year": 2016}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 10.0, "year": 2016}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 2.0, "year": 2016}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2016}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2016}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2016}, {"source": "44", "target": "66", "source_name": "phase diagram", "target_name": "sulfur hydride", "weight": 4.0, "year": 2016}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2016}, {"source": "44", "target": "69", "source_name": "phase diagram", "target_name": "selenium hydrides", "weight": 5.0, "year": 2016}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2016}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 2.0, "year": 2016}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2016}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2016}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 6.0, "year": 2016}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2016}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2016}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2016}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2016}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 1.0, "year": 2016}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2016}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2016}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2016}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2016}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2016}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 5.0, "year": 2016}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2016}, {"source": "47", "target": "66", "source_name": "magnetic susceptibility", "target_name": "sulfur hydride", "weight": 1.0, "year": 2016}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 2.0, "year": 2016}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 3.0, "year": 2016}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 3.0, "year": 2016}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "47", "target": "91", "source_name": "magnetic susceptibility", "target_name": "heat capacity", "weight": 1.0, "year": 2016}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 6.0, "year": 2016}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2016}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 2.0, "year": 2016}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2016}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2016}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2016}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 6.0, "year": 2016}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2016}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2016}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 10.0, "year": 2016}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 8.0, "year": 2016}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2016}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2016}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2016}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 4.0, "year": 2016}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2016}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2016}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2016}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2016}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2016}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2016}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2016}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2016}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 2.0, "year": 2016}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2016}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 3.0, "year": 2016}, {"source": "52", "target": "73", "source_name": "hydrogen sulfide", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2016}, {"source": "53", "target": "55", "source_name": "spectral weight", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 3.0, "year": 2016}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2016}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 4.0, "year": 2016}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2016}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 6.0, "year": 2016}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2016}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 2.0, "year": 2016}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2016}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 2.0, "year": 2016}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2016}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2016}, {"source": "54", "target": "79", "source_name": "coherence length", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 5.0, "year": 2016}, {"source": "54", "target": "91", "source_name": "coherence length", "target_name": "heat capacity", "weight": 2.0, "year": 2016}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2016}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2016}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2016}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2016}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 9.0, "year": 2016}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 2.0, "year": 2016}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2016}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "57", "target": "69", "source_name": "density functional theory", "target_name": "selenium hydrides", "weight": 2.0, "year": 2016}, {"source": "57", "target": "79", "source_name": "density functional theory", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "57", "target": "90", "source_name": "density functional theory", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "58", "target": "62", "source_name": "single crystal", "target_name": "alternating current", "weight": 1.0, "year": 2016}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 3.0, "year": 2016}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2016}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2016}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 2.0, "year": 2016}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 4.0, "year": 2016}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "58", "target": "84", "source_name": "single crystal", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 4.0, "year": 2016}, {"source": "58", "target": "91", "source_name": "single crystal", "target_name": "heat capacity", "weight": 3.0, "year": 2016}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 3.0, "year": 2016}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2016}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "61", "target": "64", "source_name": "synchronous motor", "target_name": "liquid helium", "weight": 1.0, "year": 2016}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 2.0, "year": 2016}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 2.0, "year": 2016}, {"source": "62", "target": "65", "source_name": "alternating current", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "62", "target": "77", "source_name": "alternating current", "target_name": "magnetic levitation", "weight": 1.0, "year": 2016}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "62", "target": "83", "source_name": "alternating current", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "62", "target": "91", "source_name": "alternating current", "target_name": "heat capacity", "weight": 1.0, "year": 2016}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2016}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2016}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2016}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2016}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2016}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2016}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2016}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2016}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2016}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2016}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2016}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2016}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2016}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 3.0, "year": 2016}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 3.0, "year": 2016}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2016}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 5.0, "year": 2016}, {"source": "65", "target": "91", "source_name": "copper oxide", "target_name": "heat capacity", "weight": 1.0, "year": 2016}, {"source": "66", "target": "69", "source_name": "sulfur hydride", "target_name": "selenium hydrides", "weight": 4.0, "year": 2016}, {"source": "66", "target": "70", "source_name": "sulfur hydride", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "66", "target": "73", "source_name": "sulfur hydride", "target_name": "room temperature", "weight": 1.0, "year": 2016}, {"source": "66", "target": "79", "source_name": "sulfur hydride", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2016}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2016}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2016}, {"source": "67", "target": "88", "source_name": "magnesium diboride", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2016}, {"source": "68", "target": "79", "source_name": "nuclear magnetic resonance", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 3.0, "year": 2016}, {"source": "70", "target": "79", "source_name": "meissner effect", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2016}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 3.0, "year": 2016}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2016}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 3.0, "year": 2016}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2016}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2016}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2016}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2016}, {"source": "73", "target": "79", "source_name": "room temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2016}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2016}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2016}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2016}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 3.0, "year": 2016}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2016}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2016}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2016}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2016}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 6.0, "year": 2016}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2016}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2016}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2016}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "79", "target": "84", "source_name": "crystal structure", "target_name": "ground state", "weight": 2.0, "year": 2016}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2016}, {"source": "79", "target": "90", "source_name": "crystal structure", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "79", "target": "91", "source_name": "crystal structure", "target_name": "heat capacity", "weight": 2.0, "year": 2016}, {"source": "79", "target": "92", "source_name": "crystal structure", "target_name": "ab initio", "weight": 1.0, "year": 2016}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2016}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 2.0, "year": 2016}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 1.0, "year": 2016}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 3.0, "year": 2016}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2016}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2016}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2016}]}, {"2017": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2017}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2017}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2017}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2017}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 3.0, "year": 2017}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2017}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2017}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 19.0, "year": 2017}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2017}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 3.0, "year": 2017}, {"source": "1", "target": "5", "source_name": "critical temperature", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2017}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 2.0, "year": 2017}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 10.0, "year": 2017}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2017}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2017}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2017}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 2.0, "year": 2017}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2017}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 10.0, "year": 2017}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2017}, {"source": "1", "target": "18", "source_name": "critical temperature", "target_name": "fermi arcs", "weight": 5.0, "year": 2017}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 4.0, "year": 2017}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 14.0, "year": 2017}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 4.0, "year": 2017}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 3.0, "year": 2017}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 6.0, "year": 2017}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2017}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 11.0, "year": 2017}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 4.0, "year": 2017}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2017}, {"source": "1", "target": "33", "source_name": "critical temperature", "target_name": "strontium titanate", "weight": 4.0, "year": 2017}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 10.0, "year": 2017}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 3.0, "year": 2017}, {"source": "1", "target": "36", "source_name": "critical temperature", "target_name": "ion beam", "weight": 1.0, "year": 2017}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 8.0, "year": 2017}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2017}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 28.0, "year": 2017}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 4.0, "year": 2017}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2017}, {"source": "1", "target": "43", "source_name": "critical temperature", "target_name": "transmission electron microscopy", "weight": 5.0, "year": 2017}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 8.0, "year": 2017}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 3.0, "year": 2017}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2017}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 10.0, "year": 2017}, {"source": "1", "target": "52", "source_name": "critical temperature", "target_name": "hydrogen sulfide", "weight": 3.0, "year": 2017}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 7.0, "year": 2017}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 5.0, "year": 2017}, {"source": "1", "target": "57", "source_name": "critical temperature", "target_name": "density functional theory", "weight": 4.0, "year": 2017}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 12.0, "year": 2017}, {"source": "1", "target": "59", "source_name": "critical temperature", "target_name": "monte carlo", "weight": 3.0, "year": 2017}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2017}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 21.0, "year": 2017}, {"source": "1", "target": "66", "source_name": "critical temperature", "target_name": "sulfur hydride", "weight": 7.0, "year": 2017}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2017}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 6.0, "year": 2017}, {"source": "1", "target": "69", "source_name": "critical temperature", "target_name": "selenium hydrides", "weight": 2.0, "year": 2017}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2017}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 7.0, "year": 2017}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 9.0, "year": 2017}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2017}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 4.0, "year": 2017}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 6.0, "year": 2017}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 3.0, "year": 2017}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2017}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2017}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2017}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2017}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 12.0, "year": 2017}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2017}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 5.0, "year": 2017}, {"source": "2", "target": "4", "source_name": "current density", "target_name": "penetration depth", "weight": 1.0, "year": 2017}, {"source": "2", "target": "5", "source_name": "current density", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2017}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2017}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2017}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 7.0, "year": 2017}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2017}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2017}, {"source": "2", "target": "14", "source_name": "current density", "target_name": "iron selenide", "weight": 1.0, "year": 2017}, {"source": "2", "target": "15", "source_name": "current density", "target_name": "magnetic flux", "weight": 1.0, "year": 2017}, {"source": "2", "target": "17", "source_name": "current density", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2017}, {"source": "2", "target": "18", "source_name": "current density", "target_name": "fermi arcs", "weight": 5.0, "year": 2017}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2017}, {"source": "2", "target": "20", "source_name": "current density", "target_name": "specific heat", "weight": 6.0, "year": 2017}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 3.0, "year": 2017}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2017}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2017}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 1.0, "year": 2017}, {"source": "2", "target": "28", "source_name": "current density", "target_name": "bcs theory", "weight": 1.0, "year": 2017}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2017}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2017}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 2.0, "year": 2017}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2017}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 37.0, "year": 2017}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 4.0, "year": 2017}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2017}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "2", "target": "45", "source_name": "current density", "target_name": "power transmission", "weight": 1.0, "year": 2017}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 5.0, "year": 2017}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 2.0, "year": 2017}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 5.0, "year": 2017}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 3.0, "year": 2017}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 1.0, "year": 2017}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2017}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 2.0, "year": 2017}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 8.0, "year": 2017}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2017}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2017}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 2.0, "year": 2017}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 8.0, "year": 2017}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2017}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 6.0, "year": 2017}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2017}, {"source": "2", "target": "79", "source_name": "current density", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "2", "target": "80", "source_name": "current density", "target_name": "quench propagation", "weight": 1.0, "year": 2017}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2017}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 4.0, "year": 2017}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2017}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 2.0, "year": 2017}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2017}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 2.0, "year": 2017}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2017}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2017}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2017}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "3", "target": "73", "source_name": "charge density waves", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "4", "target": "14", "source_name": "penetration depth", "target_name": "iron selenide", "weight": 1.0, "year": 2017}, {"source": "4", "target": "17", "source_name": "penetration depth", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2017}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2017}, {"source": "4", "target": "20", "source_name": "penetration depth", "target_name": "specific heat", "weight": 1.0, "year": 2017}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2017}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 2.0, "year": 2017}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 4.0, "year": 2017}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2017}, {"source": "4", "target": "55", "source_name": "penetration depth", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 2.0, "year": 2017}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 2.0, "year": 2017}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2017}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "5", "target": "23", "source_name": "chemical vapor deposition", "target_name": "order parameter", "weight": 1.0, "year": 2017}, {"source": "5", "target": "36", "source_name": "chemical vapor deposition", "target_name": "ion beam", "weight": 1.0, "year": 2017}, {"source": "5", "target": "40", "source_name": "chemical vapor deposition", "target_name": "magnetic field", "weight": 1.0, "year": 2017}, {"source": "5", "target": "88", "source_name": "chemical vapor deposition", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2017}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2017}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2017}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 4.0, "year": 2017}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2017}, {"source": "6", "target": "34", "source_name": "brillouin zone", "target_name": "exchange interaction", "weight": 1.0, "year": 2017}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 5.0, "year": 2017}, {"source": "6", "target": "44", "source_name": "brillouin zone", "target_name": "phase diagram", "weight": 4.0, "year": 2017}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2017}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 4.0, "year": 2017}, {"source": "6", "target": "57", "source_name": "brillouin zone", "target_name": "density functional theory", "weight": 1.0, "year": 2017}, {"source": "6", "target": "79", "source_name": "brillouin zone", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 3.0, "year": 2017}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 4.0, "year": 2017}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2017}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2017}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2017}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2017}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2017}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 5.0, "year": 2017}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2017}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2017}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 4.0, "year": 2017}, {"source": "7", "target": "59", "source_name": "kinetic energy", "target_name": "monte carlo", "weight": 1.0, "year": 2017}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2017}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2017}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "8", "target": "22", "source_name": "symmetry breaking", "target_name": "unit cell", "weight": 1.0, "year": 2017}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2017}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2017}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2017}, {"source": "9", "target": "17", "source_name": "condensed matter physics", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2017}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 2.0, "year": 2017}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2017}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2017}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 22.0, "year": 2017}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 1.0, "year": 2017}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2017}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2017}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2017}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2017}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2017}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2017}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2017}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2017}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "9", "target": "73", "source_name": "condensed matter physics", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2017}, {"source": "9", "target": "87", "source_name": "condensed matter physics", "target_name": "charge transfer", "weight": 4.0, "year": 2017}, {"source": "9", "target": "90", "source_name": "condensed matter physics", "target_name": "cooper pair", "weight": 4.0, "year": 2017}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2017}, {"source": "10", "target": "13", "source_name": "liquid nitrogen", "target_name": "josephson junctions", "weight": 1.0, "year": 2017}, {"source": "10", "target": "14", "source_name": "liquid nitrogen", "target_name": "iron selenide", "weight": 1.0, "year": 2017}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2017}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 2.0, "year": 2017}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2017}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2017}, {"source": "10", "target": "22", "source_name": "liquid nitrogen", "target_name": "unit cell", "weight": 1.0, "year": 2017}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2017}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2017}, {"source": "10", "target": "33", "source_name": "liquid nitrogen", "target_name": "strontium titanate", "weight": 1.0, "year": 2017}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 2.0, "year": 2017}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2017}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 20.0, "year": 2017}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2017}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2017}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2017}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 5.0, "year": 2017}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2017}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 3.0, "year": 2017}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2017}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2017}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2017}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2017}, {"source": "10", "target": "66", "source_name": "liquid nitrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2017}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2017}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2017}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 2.0, "year": 2017}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 4.0, "year": 2017}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2017}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2017}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2017}, {"source": "10", "target": "80", "source_name": "liquid nitrogen", "target_name": "quench propagation", "weight": 1.0, "year": 2017}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 3.0, "year": 2017}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2017}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 5.0, "year": 2017}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 2.0, "year": 2017}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2017}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2017}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 2.0, "year": 2017}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2017}, {"source": "11", "target": "51", "source_name": "yttrium barium copper oxide", "target_name": "wind turbine", "weight": 1.0, "year": 2017}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 7.0, "year": 2017}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2017}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 6.0, "year": 2017}, {"source": "12", "target": "19", "source_name": "scanning tunneling microscopy", "target_name": "electric field", "weight": 2.0, "year": 2017}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2017}, {"source": "12", "target": "22", "source_name": "scanning tunneling microscopy", "target_name": "unit cell", "weight": 5.0, "year": 2017}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 6.0, "year": 2017}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2017}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2017}, {"source": "12", "target": "58", "source_name": "scanning tunneling microscopy", "target_name": "single crystal", "weight": 3.0, "year": 2017}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2017}, {"source": "12", "target": "60", "source_name": "scanning tunneling microscopy", "target_name": "mott insulator", "weight": 1.0, "year": 2017}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "12", "target": "87", "source_name": "scanning tunneling microscopy", "target_name": "charge transfer", "weight": 3.0, "year": 2017}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2017}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2017}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2017}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 3.0, "year": 2017}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2017}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2017}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2017}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 2.0, "year": 2017}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2017}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2017}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2017}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2017}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "14", "target": "20", "source_name": "iron selenide", "target_name": "specific heat", "weight": 1.0, "year": 2017}, {"source": "14", "target": "22", "source_name": "iron selenide", "target_name": "unit cell", "weight": 1.0, "year": 2017}, {"source": "14", "target": "28", "source_name": "iron selenide", "target_name": "bcs theory", "weight": 1.0, "year": 2017}, {"source": "14", "target": "33", "source_name": "iron selenide", "target_name": "strontium titanate", "weight": 3.0, "year": 2017}, {"source": "14", "target": "40", "source_name": "iron selenide", "target_name": "magnetic field", "weight": 1.0, "year": 2017}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 2.0, "year": 2017}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2017}, {"source": "15", "target": "20", "source_name": "magnetic flux", "target_name": "specific heat", "weight": 1.0, "year": 2017}, {"source": "15", "target": "23", "source_name": "magnetic flux", "target_name": "order parameter", "weight": 1.0, "year": 2017}, {"source": "15", "target": "32", "source_name": "magnetic flux", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2017}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2017}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 10.0, "year": 2017}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 2.0, "year": 2017}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 2.0, "year": 2017}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 3.0, "year": 2017}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2017}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "15", "target": "83", "source_name": "magnetic flux", "target_name": "permanent magnet", "weight": 1.0, "year": 2017}, {"source": "15", "target": "88", "source_name": "magnetic flux", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 2.0, "year": 2017}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2017}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2017}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2017}, {"source": "16", "target": "34", "source_name": "coulomb repulsion", "target_name": "exchange interaction", "weight": 4.0, "year": 2017}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2017}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 7.0, "year": 2017}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 6.0, "year": 2017}, {"source": "16", "target": "59", "source_name": "coulomb repulsion", "target_name": "monte carlo", "weight": 3.0, "year": 2017}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2017}, {"source": "16", "target": "72", "source_name": "coulomb repulsion", "target_name": "electrical resistance", "weight": 1.0, "year": 2017}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2017}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2017}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2017}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2017}, {"source": "17", "target": "19", "source_name": "molecular beam epitaxy", "target_name": "electric field", "weight": 3.0, "year": 2017}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 5.0, "year": 2017}, {"source": "17", "target": "31", "source_name": "molecular beam epitaxy", "target_name": "condensed matter", "weight": 4.0, "year": 2017}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 7.0, "year": 2017}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2017}, {"source": "17", "target": "54", "source_name": "molecular beam epitaxy", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 4.0, "year": 2017}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 2.0, "year": 2017}, {"source": "17", "target": "70", "source_name": "molecular beam epitaxy", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 6.0, "year": 2017}, {"source": "17", "target": "90", "source_name": "molecular beam epitaxy", "target_name": "cooper pair", "weight": 5.0, "year": 2017}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 7.0, "year": 2017}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2017}, {"source": "18", "target": "30", "source_name": "fermi arcs", "target_name": "fermi level", "weight": 1.0, "year": 2017}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2017}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 7.0, "year": 2017}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2017}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 7.0, "year": 2017}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2017}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2017}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 10.0, "year": 2017}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 3.0, "year": 2017}, {"source": "19", "target": "87", "source_name": "electric field", "target_name": "charge transfer", "weight": 1.0, "year": 2017}, {"source": "20", "target": "22", "source_name": "specific heat", "target_name": "unit cell", "weight": 1.0, "year": 2017}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 3.0, "year": 2017}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 4.0, "year": 2017}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 6.0, "year": 2017}, {"source": "20", "target": "35", "source_name": "specific heat", "target_name": "space group", "weight": 2.0, "year": 2017}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 3.0, "year": 2017}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 12.0, "year": 2017}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2017}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2017}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 6.0, "year": 2017}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2017}, {"source": "20", "target": "54", "source_name": "specific heat", "target_name": "coherence length", "weight": 2.0, "year": 2017}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2017}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 9.0, "year": 2017}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 7.0, "year": 2017}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2017}, {"source": "20", "target": "79", "source_name": "specific heat", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2017}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 2.0, "year": 2017}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 4.0, "year": 2017}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 3.0, "year": 2017}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2017}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "21", "target": "46", "source_name": "grain boundary", "target_name": "iron pnictides", "weight": 1.0, "year": 2017}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "22", "target": "28", "source_name": "unit cell", "target_name": "bcs theory", "weight": 1.0, "year": 2017}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 2.0, "year": 2017}, {"source": "22", "target": "33", "source_name": "unit cell", "target_name": "strontium titanate", "weight": 1.0, "year": 2017}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 4.0, "year": 2017}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "22", "target": "58", "source_name": "unit cell", "target_name": "single crystal", "weight": 3.0, "year": 2017}, {"source": "22", "target": "70", "source_name": "unit cell", "target_name": "meissner effect", "weight": 2.0, "year": 2017}, {"source": "22", "target": "73", "source_name": "unit cell", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "22", "target": "87", "source_name": "unit cell", "target_name": "charge transfer", "weight": 2.0, "year": 2017}, {"source": "23", "target": "26", "source_name": "order parameter", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2017}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2017}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2017}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2017}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2017}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2017}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 4.0, "year": 2017}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 3.0, "year": 2017}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2017}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2017}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2017}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 3.0, "year": 2017}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2017}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 2.0, "year": 2017}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2017}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2017}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2017}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2017}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2017}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2017}, {"source": "23", "target": "73", "source_name": "order parameter", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2017}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2017}, {"source": "23", "target": "88", "source_name": "order parameter", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 6.0, "year": 2017}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 3.0, "year": 2017}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2017}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2017}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "24", "target": "64", "source_name": "magnetic resonance imaging", "target_name": "liquid helium", "weight": 1.0, "year": 2017}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2017}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2017}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 2.0, "year": 2017}, {"source": "24", "target": "88", "source_name": "magnetic resonance imaging", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "26", "target": "30", "source_name": "carbon nanotubes", "target_name": "fermi level", "weight": 1.0, "year": 2017}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2017}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "26", "target": "71", "source_name": "carbon nanotubes", "target_name": "van hove", "weight": 1.0, "year": 2017}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 2.0, "year": 2017}, {"source": "26", "target": "90", "source_name": "carbon nanotubes", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 3.0, "year": 2017}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2017}, {"source": "27", "target": "45", "source_name": "ac losses", "target_name": "power transmission", "weight": 1.0, "year": 2017}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2017}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2017}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2017}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2017}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2017}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 3.0, "year": 2017}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2017}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 5.0, "year": 2017}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2017}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2017}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2017}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2017}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2017}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2017}, {"source": "28", "target": "58", "source_name": "bcs theory", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2017}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 1.0, "year": 2017}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2017}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2017}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2017}, {"source": "28", "target": "79", "source_name": "bcs theory", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2017}, {"source": "28", "target": "92", "source_name": "bcs theory", "target_name": "ab initio", "weight": 1.0, "year": 2017}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2017}, {"source": "29", "target": "44", "source_name": "raman scattering", "target_name": "phase diagram", "weight": 2.0, "year": 2017}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2017}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 4.0, "year": 2017}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2017}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 3.0, "year": 2017}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2017}, {"source": "30", "target": "47", "source_name": "fermi level", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2017}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2017}, {"source": "30", "target": "54", "source_name": "fermi level", "target_name": "coherence length", "weight": 2.0, "year": 2017}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 1.0, "year": 2017}, {"source": "30", "target": "58", "source_name": "fermi level", "target_name": "single crystal", "weight": 2.0, "year": 2017}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 3.0, "year": 2017}, {"source": "30", "target": "72", "source_name": "fermi level", "target_name": "electrical resistance", "weight": 1.0, "year": 2017}, {"source": "30", "target": "73", "source_name": "fermi level", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "30", "target": "79", "source_name": "fermi level", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "30", "target": "91", "source_name": "fermi level", "target_name": "heat capacity", "weight": 2.0, "year": 2017}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2017}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2017}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2017}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 2.0, "year": 2017}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2017}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "31", "target": "58", "source_name": "condensed matter", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2017}, {"source": "31", "target": "62", "source_name": "condensed matter", "target_name": "alternating current", "weight": 1.0, "year": 2017}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2017}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 3.0, "year": 2017}, {"source": "31", "target": "73", "source_name": "condensed matter", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2017}, {"source": "31", "target": "87", "source_name": "condensed matter", "target_name": "charge transfer", "weight": 4.0, "year": 2017}, {"source": "31", "target": "90", "source_name": "condensed matter", "target_name": "cooper pair", "weight": 4.0, "year": 2017}, {"source": "31", "target": "91", "source_name": "condensed matter", "target_name": "heat capacity", "weight": 1.0, "year": 2017}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2017}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2017}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 3.0, "year": 2017}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 8.0, "year": 2017}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2017}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 4.0, "year": 2017}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2017}, {"source": "34", "target": "49", "source_name": "exchange interaction", "target_name": "strongly correlated", "weight": 4.0, "year": 2017}, {"source": "34", "target": "56", "source_name": "exchange interaction", "target_name": "hubbard model", "weight": 3.0, "year": 2017}, {"source": "34", "target": "57", "source_name": "exchange interaction", "target_name": "density functional theory", "weight": 1.0, "year": 2017}, {"source": "34", "target": "59", "source_name": "exchange interaction", "target_name": "monte carlo", "weight": 3.0, "year": 2017}, {"source": "34", "target": "66", "source_name": "exchange interaction", "target_name": "sulfur hydride", "weight": 2.0, "year": 2017}, {"source": "34", "target": "72", "source_name": "exchange interaction", "target_name": "electrical resistance", "weight": 1.0, "year": 2017}, {"source": "34", "target": "79", "source_name": "exchange interaction", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 2.0, "year": 2017}, {"source": "35", "target": "47", "source_name": "space group", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2017}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 3.0, "year": 2017}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2017}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2017}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2017}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2017}, {"source": "36", "target": "54", "source_name": "ion beam", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2017}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2017}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2017}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 3.0, "year": 2017}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2017}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2017}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2017}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 4.0, "year": 2017}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2017}, {"source": "37", "target": "57", "source_name": "fermi surface", "target_name": "density functional theory", "weight": 1.0, "year": 2017}, {"source": "37", "target": "58", "source_name": "fermi surface", "target_name": "single crystal", "weight": 2.0, "year": 2017}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2017}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2017}, {"source": "37", "target": "68", "source_name": "fermi surface", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2017}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 5.0, "year": 2017}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 8.0, "year": 2017}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2017}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2017}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 8.0, "year": 2017}, {"source": "37", "target": "91", "source_name": "fermi surface", "target_name": "heat capacity", "weight": 2.0, "year": 2017}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2017}, {"source": "38", "target": "66", "source_name": "metallic hydrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2017}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "38", "target": "79", "source_name": "metallic hydrogen", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2017}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 3.0, "year": 2017}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 8.0, "year": 2017}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2017}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 1.0, "year": 2017}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 2.0, "year": 2017}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2017}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 11.0, "year": 2017}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 2.0, "year": 2017}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 3.0, "year": 2017}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 3.0, "year": 2017}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 9.0, "year": 2017}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 6.0, "year": 2017}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2017}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2017}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 13.0, "year": 2017}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 3.0, "year": 2017}, {"source": "40", "target": "52", "source_name": "magnetic field", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2017}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2017}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2017}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 18.0, "year": 2017}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 9.0, "year": 2017}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 2.0, "year": 2017}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2017}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 16.0, "year": 2017}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 11.0, "year": 2017}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2017}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2017}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 3.0, "year": 2017}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 15.0, "year": 2017}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2017}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2017}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 9.0, "year": 2017}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 4.0, "year": 2017}, {"source": "40", "target": "79", "source_name": "magnetic field", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 4.0, "year": 2017}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 8.0, "year": 2017}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 11.0, "year": 2017}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 5.0, "year": 2017}, {"source": "40", "target": "87", "source_name": "magnetic field", "target_name": "charge transfer", "weight": 1.0, "year": 2017}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 13.0, "year": 2017}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 3.0, "year": 2017}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2017}, {"source": "41", "target": "46", "source_name": "grain boundaries", "target_name": "iron pnictides", "weight": 1.0, "year": 2017}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2017}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2017}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 2.0, "year": 2017}, {"source": "41", "target": "79", "source_name": "grain boundaries", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2017}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2017}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2017}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2017}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "43", "target": "68", "source_name": "transmission electron microscopy", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2017}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2017}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 4.0, "year": 2017}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2017}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 6.0, "year": 2017}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 4.0, "year": 2017}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2017}, {"source": "44", "target": "53", "source_name": "phase diagram", "target_name": "spectral weight", "weight": 1.0, "year": 2017}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2017}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 6.0, "year": 2017}, {"source": "44", "target": "57", "source_name": "phase diagram", "target_name": "density functional theory", "weight": 2.0, "year": 2017}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 10.0, "year": 2017}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 2.0, "year": 2017}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2017}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2017}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2017}, {"source": "44", "target": "66", "source_name": "phase diagram", "target_name": "sulfur hydride", "weight": 4.0, "year": 2017}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2017}, {"source": "44", "target": "69", "source_name": "phase diagram", "target_name": "selenium hydrides", "weight": 5.0, "year": 2017}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2017}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 2.0, "year": 2017}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2017}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2017}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2017}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 6.0, "year": 2017}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2017}, {"source": "44", "target": "92", "source_name": "phase diagram", "target_name": "ab initio", "weight": 1.0, "year": 2017}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2017}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2017}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2017}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 2.0, "year": 2017}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2017}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2017}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2017}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2017}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2017}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 5.0, "year": 2017}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2017}, {"source": "47", "target": "66", "source_name": "magnetic susceptibility", "target_name": "sulfur hydride", "weight": 1.0, "year": 2017}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 2.0, "year": 2017}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 3.0, "year": 2017}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 3.0, "year": 2017}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "47", "target": "91", "source_name": "magnetic susceptibility", "target_name": "heat capacity", "weight": 1.0, "year": 2017}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 6.0, "year": 2017}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2017}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 2.0, "year": 2017}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2017}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2017}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2017}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 6.0, "year": 2017}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2017}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2017}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 10.0, "year": 2017}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 8.0, "year": 2017}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2017}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 2.0, "year": 2017}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2017}, {"source": "49", "target": "73", "source_name": "strongly correlated", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2017}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 4.0, "year": 2017}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2017}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2017}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2017}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2017}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2017}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2017}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2017}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2017}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 2.0, "year": 2017}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 2.0, "year": 2017}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2017}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 3.0, "year": 2017}, {"source": "52", "target": "66", "source_name": "hydrogen sulfide", "target_name": "sulfur hydride", "weight": 1.0, "year": 2017}, {"source": "52", "target": "73", "source_name": "hydrogen sulfide", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2017}, {"source": "53", "target": "55", "source_name": "spectral weight", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 3.0, "year": 2017}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2017}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 4.0, "year": 2017}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2017}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 6.0, "year": 2017}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2017}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 2.0, "year": 2017}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2017}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 2.0, "year": 2017}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2017}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2017}, {"source": "54", "target": "79", "source_name": "coherence length", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 5.0, "year": 2017}, {"source": "54", "target": "91", "source_name": "coherence length", "target_name": "heat capacity", "weight": 2.0, "year": 2017}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2017}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2017}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2017}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2017}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 10.0, "year": 2017}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 3.0, "year": 2017}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2017}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "57", "target": "69", "source_name": "density functional theory", "target_name": "selenium hydrides", "weight": 2.0, "year": 2017}, {"source": "57", "target": "79", "source_name": "density functional theory", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "57", "target": "90", "source_name": "density functional theory", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "57", "target": "92", "source_name": "density functional theory", "target_name": "ab initio", "weight": 1.0, "year": 2017}, {"source": "58", "target": "62", "source_name": "single crystal", "target_name": "alternating current", "weight": 1.0, "year": 2017}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 3.0, "year": 2017}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2017}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2017}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 2.0, "year": 2017}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 4.0, "year": 2017}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2017}, {"source": "58", "target": "84", "source_name": "single crystal", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 5.0, "year": 2017}, {"source": "58", "target": "91", "source_name": "single crystal", "target_name": "heat capacity", "weight": 3.0, "year": 2017}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 4.0, "year": 2017}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2017}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "61", "target": "64", "source_name": "synchronous motor", "target_name": "liquid helium", "weight": 1.0, "year": 2017}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 2.0, "year": 2017}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 2.0, "year": 2017}, {"source": "62", "target": "65", "source_name": "alternating current", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "62", "target": "77", "source_name": "alternating current", "target_name": "magnetic levitation", "weight": 1.0, "year": 2017}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "62", "target": "83", "source_name": "alternating current", "target_name": "permanent magnet", "weight": 1.0, "year": 2017}, {"source": "62", "target": "91", "source_name": "alternating current", "target_name": "heat capacity", "weight": 1.0, "year": 2017}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2017}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2017}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2017}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2017}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2017}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2017}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2017}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2017}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2017}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2017}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2017}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2017}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2017}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 4.0, "year": 2017}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 3.0, "year": 2017}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2017}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2017}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 5.0, "year": 2017}, {"source": "65", "target": "91", "source_name": "copper oxide", "target_name": "heat capacity", "weight": 1.0, "year": 2017}, {"source": "66", "target": "69", "source_name": "sulfur hydride", "target_name": "selenium hydrides", "weight": 4.0, "year": 2017}, {"source": "66", "target": "70", "source_name": "sulfur hydride", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "66", "target": "73", "source_name": "sulfur hydride", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "66", "target": "79", "source_name": "sulfur hydride", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2017}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2017}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2017}, {"source": "67", "target": "88", "source_name": "magnesium diboride", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2017}, {"source": "68", "target": "79", "source_name": "nuclear magnetic resonance", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 3.0, "year": 2017}, {"source": "70", "target": "79", "source_name": "meissner effect", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2017}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 3.0, "year": 2017}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2017}, {"source": "71", "target": "73", "source_name": "van hove", "target_name": "room temperature", "weight": 1.0, "year": 2017}, {"source": "72", "target": "73", "source_name": "electrical resistance", "target_name": "room temperature", "weight": 2.0, "year": 2017}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 3.0, "year": 2017}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2017}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2017}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2017}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2017}, {"source": "73", "target": "79", "source_name": "room temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2017}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2017}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2017}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2017}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 4.0, "year": 2017}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2017}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2017}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2017}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2017}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 6.0, "year": 2017}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2017}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2017}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2017}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "79", "target": "84", "source_name": "crystal structure", "target_name": "ground state", "weight": 2.0, "year": 2017}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2017}, {"source": "79", "target": "90", "source_name": "crystal structure", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "79", "target": "91", "source_name": "crystal structure", "target_name": "heat capacity", "weight": 2.0, "year": 2017}, {"source": "79", "target": "92", "source_name": "crystal structure", "target_name": "ab initio", "weight": 2.0, "year": 2017}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2017}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 2.0, "year": 2017}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 1.0, "year": 2017}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 3.0, "year": 2017}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2017}, {"source": "87", "target": "90", "source_name": "charge transfer", "target_name": "cooper pair", "weight": 4.0, "year": 2017}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2017}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2017}]}, {"2018": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2018}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2018}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2018}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2018}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 3.0, "year": 2018}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2018}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2018}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 22.0, "year": 2018}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2018}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 3.0, "year": 2018}, {"source": "1", "target": "5", "source_name": "critical temperature", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2018}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 2.0, "year": 2018}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 10.0, "year": 2018}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2018}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 2.0, "year": 2018}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2018}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 2.0, "year": 2018}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2018}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 10.0, "year": 2018}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2018}, {"source": "1", "target": "18", "source_name": "critical temperature", "target_name": "fermi arcs", "weight": 5.0, "year": 2018}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 4.0, "year": 2018}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 16.0, "year": 2018}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 4.0, "year": 2018}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 3.0, "year": 2018}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 7.0, "year": 2018}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2018}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 11.0, "year": 2018}, {"source": "1", "target": "29", "source_name": "critical temperature", "target_name": "raman scattering", "weight": 1.0, "year": 2018}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 7.0, "year": 2018}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2018}, {"source": "1", "target": "33", "source_name": "critical temperature", "target_name": "strontium titanate", "weight": 4.0, "year": 2018}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 10.0, "year": 2018}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 3.0, "year": 2018}, {"source": "1", "target": "36", "source_name": "critical temperature", "target_name": "ion beam", "weight": 1.0, "year": 2018}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 8.0, "year": 2018}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 2.0, "year": 2018}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 34.0, "year": 2018}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 4.0, "year": 2018}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 2.0, "year": 2018}, {"source": "1", "target": "43", "source_name": "critical temperature", "target_name": "transmission electron microscopy", "weight": 5.0, "year": 2018}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 9.0, "year": 2018}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 4.0, "year": 2018}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 7.0, "year": 2018}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 10.0, "year": 2018}, {"source": "1", "target": "52", "source_name": "critical temperature", "target_name": "hydrogen sulfide", "weight": 4.0, "year": 2018}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 7.0, "year": 2018}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 7.0, "year": 2018}, {"source": "1", "target": "57", "source_name": "critical temperature", "target_name": "density functional theory", "weight": 7.0, "year": 2018}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 13.0, "year": 2018}, {"source": "1", "target": "59", "source_name": "critical temperature", "target_name": "monte carlo", "weight": 3.0, "year": 2018}, {"source": "1", "target": "60", "source_name": "critical temperature", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2018}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 22.0, "year": 2018}, {"source": "1", "target": "66", "source_name": "critical temperature", "target_name": "sulfur hydride", "weight": 7.0, "year": 2018}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2018}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 6.0, "year": 2018}, {"source": "1", "target": "69", "source_name": "critical temperature", "target_name": "selenium hydrides", "weight": 2.0, "year": 2018}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 3.0, "year": 2018}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2018}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 7.0, "year": 2018}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 13.0, "year": 2018}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2018}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 4.0, "year": 2018}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 7.0, "year": 2018}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 5.0, "year": 2018}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2018}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2018}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2018}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2018}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 14.0, "year": 2018}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 5.0, "year": 2018}, {"source": "2", "target": "4", "source_name": "current density", "target_name": "penetration depth", "weight": 1.0, "year": 2018}, {"source": "2", "target": "5", "source_name": "current density", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2018}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2018}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2018}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 8.0, "year": 2018}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2018}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2018}, {"source": "2", "target": "14", "source_name": "current density", "target_name": "iron selenide", "weight": 1.0, "year": 2018}, {"source": "2", "target": "15", "source_name": "current density", "target_name": "magnetic flux", "weight": 1.0, "year": 2018}, {"source": "2", "target": "17", "source_name": "current density", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2018}, {"source": "2", "target": "18", "source_name": "current density", "target_name": "fermi arcs", "weight": 5.0, "year": 2018}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2018}, {"source": "2", "target": "20", "source_name": "current density", "target_name": "specific heat", "weight": 6.0, "year": 2018}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 3.0, "year": 2018}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2018}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2018}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 3.0, "year": 2018}, {"source": "2", "target": "28", "source_name": "current density", "target_name": "bcs theory", "weight": 1.0, "year": 2018}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2018}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2018}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 2.0, "year": 2018}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2018}, {"source": "2", "target": "39", "source_name": "current density", "target_name": "finite element method", "weight": 1.0, "year": 2018}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 42.0, "year": 2018}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 4.0, "year": 2018}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2018}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "2", "target": "45", "source_name": "current density", "target_name": "power transmission", "weight": 1.0, "year": 2018}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 5.0, "year": 2018}, {"source": "2", "target": "51", "source_name": "current density", "target_name": "wind turbine", "weight": 1.0, "year": 2018}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 2.0, "year": 2018}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 6.0, "year": 2018}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 3.0, "year": 2018}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 2.0, "year": 2018}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2018}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 3.0, "year": 2018}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 8.0, "year": 2018}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2018}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2018}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 2.0, "year": 2018}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 8.0, "year": 2018}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2018}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 6.0, "year": 2018}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2018}, {"source": "2", "target": "79", "source_name": "current density", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "2", "target": "80", "source_name": "current density", "target_name": "quench propagation", "weight": 1.0, "year": 2018}, {"source": "2", "target": "81", "source_name": "current density", "target_name": "finite element", "weight": 2.0, "year": 2018}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2018}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 5.0, "year": 2018}, {"source": "2", "target": "86", "source_name": "current density", "target_name": "induction motor", "weight": 1.0, "year": 2018}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 3.0, "year": 2018}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 2.0, "year": 2018}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2018}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 2.0, "year": 2018}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2018}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2018}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2018}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "3", "target": "73", "source_name": "charge density waves", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "4", "target": "14", "source_name": "penetration depth", "target_name": "iron selenide", "weight": 1.0, "year": 2018}, {"source": "4", "target": "17", "source_name": "penetration depth", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2018}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2018}, {"source": "4", "target": "20", "source_name": "penetration depth", "target_name": "specific heat", "weight": 1.0, "year": 2018}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2018}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 2.0, "year": 2018}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 4.0, "year": 2018}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2018}, {"source": "4", "target": "55", "source_name": "penetration depth", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 2.0, "year": 2018}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2018}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "5", "target": "23", "source_name": "chemical vapor deposition", "target_name": "order parameter", "weight": 1.0, "year": 2018}, {"source": "5", "target": "36", "source_name": "chemical vapor deposition", "target_name": "ion beam", "weight": 1.0, "year": 2018}, {"source": "5", "target": "40", "source_name": "chemical vapor deposition", "target_name": "magnetic field", "weight": 1.0, "year": 2018}, {"source": "5", "target": "88", "source_name": "chemical vapor deposition", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 1.0, "year": 2018}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 1.0, "year": 2018}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2018}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 4.0, "year": 2018}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 1.0, "year": 2018}, {"source": "6", "target": "34", "source_name": "brillouin zone", "target_name": "exchange interaction", "weight": 1.0, "year": 2018}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 5.0, "year": 2018}, {"source": "6", "target": "44", "source_name": "brillouin zone", "target_name": "phase diagram", "weight": 4.0, "year": 2018}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2018}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 4.0, "year": 2018}, {"source": "6", "target": "57", "source_name": "brillouin zone", "target_name": "density functional theory", "weight": 1.0, "year": 2018}, {"source": "6", "target": "79", "source_name": "brillouin zone", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 3.0, "year": 2018}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 4.0, "year": 2018}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2018}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2018}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2018}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2018}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2018}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 5.0, "year": 2018}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2018}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2018}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 4.0, "year": 2018}, {"source": "7", "target": "59", "source_name": "kinetic energy", "target_name": "monte carlo", "weight": 1.0, "year": 2018}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2018}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2018}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "8", "target": "22", "source_name": "symmetry breaking", "target_name": "unit cell", "weight": 1.0, "year": 2018}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2018}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2018}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2018}, {"source": "9", "target": "17", "source_name": "condensed matter physics", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2018}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 2.0, "year": 2018}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2018}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2018}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 23.0, "year": 2018}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 1.0, "year": 2018}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2018}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2018}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2018}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2018}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2018}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2018}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "9", "target": "58", "source_name": "condensed matter physics", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2018}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "9", "target": "73", "source_name": "condensed matter physics", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2018}, {"source": "9", "target": "87", "source_name": "condensed matter physics", "target_name": "charge transfer", "weight": 4.0, "year": 2018}, {"source": "9", "target": "90", "source_name": "condensed matter physics", "target_name": "cooper pair", "weight": 4.0, "year": 2018}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2018}, {"source": "10", "target": "13", "source_name": "liquid nitrogen", "target_name": "josephson junctions", "weight": 1.0, "year": 2018}, {"source": "10", "target": "14", "source_name": "liquid nitrogen", "target_name": "iron selenide", "weight": 1.0, "year": 2018}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2018}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 2.0, "year": 2018}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2018}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2018}, {"source": "10", "target": "22", "source_name": "liquid nitrogen", "target_name": "unit cell", "weight": 1.0, "year": 2018}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2018}, {"source": "10", "target": "27", "source_name": "liquid nitrogen", "target_name": "ac losses", "weight": 1.0, "year": 2018}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2018}, {"source": "10", "target": "33", "source_name": "liquid nitrogen", "target_name": "strontium titanate", "weight": 1.0, "year": 2018}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 2.0, "year": 2018}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 1.0, "year": 2018}, {"source": "10", "target": "39", "source_name": "liquid nitrogen", "target_name": "finite element method", "weight": 1.0, "year": 2018}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 21.0, "year": 2018}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2018}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 1.0, "year": 2018}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2018}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 5.0, "year": 2018}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2018}, {"source": "10", "target": "51", "source_name": "liquid nitrogen", "target_name": "wind turbine", "weight": 1.0, "year": 2018}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 3.0, "year": 2018}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2018}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2018}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2018}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2018}, {"source": "10", "target": "66", "source_name": "liquid nitrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2018}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2018}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2018}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 2.0, "year": 2018}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 4.0, "year": 2018}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2018}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2018}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2018}, {"source": "10", "target": "80", "source_name": "liquid nitrogen", "target_name": "quench propagation", "weight": 1.0, "year": 2018}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 2.0, "year": 2018}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 3.0, "year": 2018}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2018}, {"source": "10", "target": "86", "source_name": "liquid nitrogen", "target_name": "induction motor", "weight": 1.0, "year": 2018}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 5.0, "year": 2018}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 2.0, "year": 2018}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2018}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 2.0, "year": 2018}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2018}, {"source": "11", "target": "51", "source_name": "yttrium barium copper oxide", "target_name": "wind turbine", "weight": 1.0, "year": 2018}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 7.0, "year": 2018}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2018}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 6.0, "year": 2018}, {"source": "12", "target": "19", "source_name": "scanning tunneling microscopy", "target_name": "electric field", "weight": 2.0, "year": 2018}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2018}, {"source": "12", "target": "22", "source_name": "scanning tunneling microscopy", "target_name": "unit cell", "weight": 5.0, "year": 2018}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 6.0, "year": 2018}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2018}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2018}, {"source": "12", "target": "58", "source_name": "scanning tunneling microscopy", "target_name": "single crystal", "weight": 3.0, "year": 2018}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2018}, {"source": "12", "target": "60", "source_name": "scanning tunneling microscopy", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "12", "target": "87", "source_name": "scanning tunneling microscopy", "target_name": "charge transfer", "weight": 3.0, "year": 2018}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2018}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2018}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2018}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 3.0, "year": 2018}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2018}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2018}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2018}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 2.0, "year": 2018}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2018}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2018}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2018}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2018}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "14", "target": "20", "source_name": "iron selenide", "target_name": "specific heat", "weight": 1.0, "year": 2018}, {"source": "14", "target": "22", "source_name": "iron selenide", "target_name": "unit cell", "weight": 1.0, "year": 2018}, {"source": "14", "target": "28", "source_name": "iron selenide", "target_name": "bcs theory", "weight": 1.0, "year": 2018}, {"source": "14", "target": "33", "source_name": "iron selenide", "target_name": "strontium titanate", "weight": 3.0, "year": 2018}, {"source": "14", "target": "40", "source_name": "iron selenide", "target_name": "magnetic field", "weight": 1.0, "year": 2018}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2018}, {"source": "15", "target": "20", "source_name": "magnetic flux", "target_name": "specific heat", "weight": 1.0, "year": 2018}, {"source": "15", "target": "23", "source_name": "magnetic flux", "target_name": "order parameter", "weight": 1.0, "year": 2018}, {"source": "15", "target": "32", "source_name": "magnetic flux", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2018}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2018}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 11.0, "year": 2018}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 2.0, "year": 2018}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 2.0, "year": 2018}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 3.0, "year": 2018}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2018}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "15", "target": "83", "source_name": "magnetic flux", "target_name": "permanent magnet", "weight": 1.0, "year": 2018}, {"source": "15", "target": "88", "source_name": "magnetic flux", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 2.0, "year": 2018}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2018}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2018}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2018}, {"source": "16", "target": "34", "source_name": "coulomb repulsion", "target_name": "exchange interaction", "weight": 4.0, "year": 2018}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 2.0, "year": 2018}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 2.0, "year": 2018}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 7.0, "year": 2018}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 6.0, "year": 2018}, {"source": "16", "target": "59", "source_name": "coulomb repulsion", "target_name": "monte carlo", "weight": 3.0, "year": 2018}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "16", "target": "72", "source_name": "coulomb repulsion", "target_name": "electrical resistance", "weight": 1.0, "year": 2018}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2018}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2018}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2018}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2018}, {"source": "17", "target": "19", "source_name": "molecular beam epitaxy", "target_name": "electric field", "weight": 3.0, "year": 2018}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 5.0, "year": 2018}, {"source": "17", "target": "31", "source_name": "molecular beam epitaxy", "target_name": "condensed matter", "weight": 4.0, "year": 2018}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 8.0, "year": 2018}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2018}, {"source": "17", "target": "54", "source_name": "molecular beam epitaxy", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 4.0, "year": 2018}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 2.0, "year": 2018}, {"source": "17", "target": "70", "source_name": "molecular beam epitaxy", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 2.0, "year": 2018}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 6.0, "year": 2018}, {"source": "17", "target": "90", "source_name": "molecular beam epitaxy", "target_name": "cooper pair", "weight": 5.0, "year": 2018}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 7.0, "year": 2018}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2018}, {"source": "18", "target": "30", "source_name": "fermi arcs", "target_name": "fermi level", "weight": 1.0, "year": 2018}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2018}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 7.0, "year": 2018}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2018}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 7.0, "year": 2018}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2018}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2018}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 11.0, "year": 2018}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "19", "target": "50", "source_name": "electric field", "target_name": "coated conductor", "weight": 1.0, "year": 2018}, {"source": "19", "target": "58", "source_name": "electric field", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "19", "target": "65", "source_name": "electric field", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 3.0, "year": 2018}, {"source": "19", "target": "87", "source_name": "electric field", "target_name": "charge transfer", "weight": 1.0, "year": 2018}, {"source": "19", "target": "91", "source_name": "electric field", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "20", "target": "22", "source_name": "specific heat", "target_name": "unit cell", "weight": 1.0, "year": 2018}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 3.0, "year": 2018}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 4.0, "year": 2018}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 7.0, "year": 2018}, {"source": "20", "target": "35", "source_name": "specific heat", "target_name": "space group", "weight": 2.0, "year": 2018}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 3.0, "year": 2018}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 12.0, "year": 2018}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2018}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2018}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 6.0, "year": 2018}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2018}, {"source": "20", "target": "54", "source_name": "specific heat", "target_name": "coherence length", "weight": 2.0, "year": 2018}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2018}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 9.0, "year": 2018}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 7.0, "year": 2018}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2018}, {"source": "20", "target": "79", "source_name": "specific heat", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2018}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 2.0, "year": 2018}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 4.0, "year": 2018}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 3.0, "year": 2018}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2018}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "21", "target": "46", "source_name": "grain boundary", "target_name": "iron pnictides", "weight": 1.0, "year": 2018}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "22", "target": "28", "source_name": "unit cell", "target_name": "bcs theory", "weight": 1.0, "year": 2018}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 2.0, "year": 2018}, {"source": "22", "target": "33", "source_name": "unit cell", "target_name": "strontium titanate", "weight": 1.0, "year": 2018}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 4.0, "year": 2018}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "22", "target": "57", "source_name": "unit cell", "target_name": "density functional theory", "weight": 3.0, "year": 2018}, {"source": "22", "target": "58", "source_name": "unit cell", "target_name": "single crystal", "weight": 3.0, "year": 2018}, {"source": "22", "target": "70", "source_name": "unit cell", "target_name": "meissner effect", "weight": 2.0, "year": 2018}, {"source": "22", "target": "73", "source_name": "unit cell", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "22", "target": "87", "source_name": "unit cell", "target_name": "charge transfer", "weight": 2.0, "year": 2018}, {"source": "23", "target": "26", "source_name": "order parameter", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2018}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2018}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2018}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2018}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2018}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 2.0, "year": 2018}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 4.0, "year": 2018}, {"source": "23", "target": "41", "source_name": "order parameter", "target_name": "grain boundaries", "weight": 1.0, "year": 2018}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 3.0, "year": 2018}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2018}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2018}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2018}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 3.0, "year": 2018}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2018}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 3.0, "year": 2018}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2018}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2018}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2018}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2018}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2018}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2018}, {"source": "23", "target": "73", "source_name": "order parameter", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2018}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2018}, {"source": "23", "target": "88", "source_name": "order parameter", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 6.0, "year": 2018}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 3.0, "year": 2018}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2018}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 1.0, "year": 2018}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "24", "target": "64", "source_name": "magnetic resonance imaging", "target_name": "liquid helium", "weight": 1.0, "year": 2018}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2018}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2018}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 2.0, "year": 2018}, {"source": "24", "target": "88", "source_name": "magnetic resonance imaging", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "26", "target": "30", "source_name": "carbon nanotubes", "target_name": "fermi level", "weight": 1.0, "year": 2018}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2018}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "26", "target": "71", "source_name": "carbon nanotubes", "target_name": "van hove", "weight": 1.0, "year": 2018}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 2.0, "year": 2018}, {"source": "26", "target": "90", "source_name": "carbon nanotubes", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "27", "target": "39", "source_name": "ac losses", "target_name": "finite element method", "weight": 1.0, "year": 2018}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 5.0, "year": 2018}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2018}, {"source": "27", "target": "45", "source_name": "ac losses", "target_name": "power transmission", "weight": 1.0, "year": 2018}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2018}, {"source": "27", "target": "51", "source_name": "ac losses", "target_name": "wind turbine", "weight": 1.0, "year": 2018}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2018}, {"source": "27", "target": "62", "source_name": "ac losses", "target_name": "alternating current", "weight": 1.0, "year": 2018}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2018}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2018}, {"source": "27", "target": "81", "source_name": "ac losses", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "27", "target": "86", "source_name": "ac losses", "target_name": "induction motor", "weight": 1.0, "year": 2018}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2018}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 3.0, "year": 2018}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2018}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 5.0, "year": 2018}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2018}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2018}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2018}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2018}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2018}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2018}, {"source": "28", "target": "58", "source_name": "bcs theory", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 1.0, "year": 2018}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2018}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2018}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2018}, {"source": "28", "target": "79", "source_name": "bcs theory", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2018}, {"source": "28", "target": "92", "source_name": "bcs theory", "target_name": "ab initio", "weight": 1.0, "year": 2018}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2018}, {"source": "29", "target": "40", "source_name": "raman scattering", "target_name": "magnetic field", "weight": 1.0, "year": 2018}, {"source": "29", "target": "44", "source_name": "raman scattering", "target_name": "phase diagram", "weight": 2.0, "year": 2018}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2018}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2018}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 4.0, "year": 2018}, {"source": "29", "target": "70", "source_name": "raman scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2018}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 3.0, "year": 2018}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2018}, {"source": "30", "target": "47", "source_name": "fermi level", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2018}, {"source": "30", "target": "54", "source_name": "fermi level", "target_name": "coherence length", "weight": 2.0, "year": 2018}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 2.0, "year": 2018}, {"source": "30", "target": "58", "source_name": "fermi level", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "30", "target": "60", "source_name": "fermi level", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "30", "target": "65", "source_name": "fermi level", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 3.0, "year": 2018}, {"source": "30", "target": "72", "source_name": "fermi level", "target_name": "electrical resistance", "weight": 1.0, "year": 2018}, {"source": "30", "target": "73", "source_name": "fermi level", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "30", "target": "79", "source_name": "fermi level", "target_name": "crystal structure", "weight": 3.0, "year": 2018}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "30", "target": "91", "source_name": "fermi level", "target_name": "heat capacity", "weight": 2.0, "year": 2018}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2018}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2018}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2018}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 2.0, "year": 2018}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2018}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "31", "target": "58", "source_name": "condensed matter", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2018}, {"source": "31", "target": "62", "source_name": "condensed matter", "target_name": "alternating current", "weight": 1.0, "year": 2018}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2018}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 3.0, "year": 2018}, {"source": "31", "target": "73", "source_name": "condensed matter", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2018}, {"source": "31", "target": "87", "source_name": "condensed matter", "target_name": "charge transfer", "weight": 4.0, "year": 2018}, {"source": "31", "target": "90", "source_name": "condensed matter", "target_name": "cooper pair", "weight": 4.0, "year": 2018}, {"source": "31", "target": "91", "source_name": "condensed matter", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2018}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2018}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 3.0, "year": 2018}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 9.0, "year": 2018}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2018}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 4.0, "year": 2018}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2018}, {"source": "34", "target": "49", "source_name": "exchange interaction", "target_name": "strongly correlated", "weight": 4.0, "year": 2018}, {"source": "34", "target": "56", "source_name": "exchange interaction", "target_name": "hubbard model", "weight": 3.0, "year": 2018}, {"source": "34", "target": "57", "source_name": "exchange interaction", "target_name": "density functional theory", "weight": 1.0, "year": 2018}, {"source": "34", "target": "59", "source_name": "exchange interaction", "target_name": "monte carlo", "weight": 3.0, "year": 2018}, {"source": "34", "target": "66", "source_name": "exchange interaction", "target_name": "sulfur hydride", "weight": 2.0, "year": 2018}, {"source": "34", "target": "72", "source_name": "exchange interaction", "target_name": "electrical resistance", "weight": 1.0, "year": 2018}, {"source": "34", "target": "79", "source_name": "exchange interaction", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 2.0, "year": 2018}, {"source": "35", "target": "47", "source_name": "space group", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2018}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 3.0, "year": 2018}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2018}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2018}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2018}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2018}, {"source": "36", "target": "54", "source_name": "ion beam", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2018}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2018}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2018}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 4.0, "year": 2018}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2018}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2018}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2018}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 4.0, "year": 2018}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2018}, {"source": "37", "target": "57", "source_name": "fermi surface", "target_name": "density functional theory", "weight": 1.0, "year": 2018}, {"source": "37", "target": "58", "source_name": "fermi surface", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2018}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2018}, {"source": "37", "target": "68", "source_name": "fermi surface", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2018}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 5.0, "year": 2018}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 8.0, "year": 2018}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2018}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2018}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 8.0, "year": 2018}, {"source": "37", "target": "91", "source_name": "fermi surface", "target_name": "heat capacity", "weight": 2.0, "year": 2018}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2018}, {"source": "38", "target": "66", "source_name": "metallic hydrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2018}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "38", "target": "79", "source_name": "metallic hydrogen", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2018}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 3.0, "year": 2018}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 11.0, "year": 2018}, {"source": "39", "target": "42", "source_name": "finite element method", "target_name": "rare earth", "weight": 1.0, "year": 2018}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2018}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 2.0, "year": 2018}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 2.0, "year": 2018}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "39", "target": "68", "source_name": "finite element method", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2018}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2018}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 15.0, "year": 2018}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 2.0, "year": 2018}, {"source": "39", "target": "86", "source_name": "finite element method", "target_name": "induction motor", "weight": 1.0, "year": 2018}, {"source": "39", "target": "88", "source_name": "finite element method", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 3.0, "year": 2018}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 4.0, "year": 2018}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 10.0, "year": 2018}, {"source": "40", "target": "46", "source_name": "magnetic field", "target_name": "iron pnictides", "weight": 1.0, "year": 2018}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 8.0, "year": 2018}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2018}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2018}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 13.0, "year": 2018}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 4.0, "year": 2018}, {"source": "40", "target": "52", "source_name": "magnetic field", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2018}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2018}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2018}, {"source": "40", "target": "57", "source_name": "magnetic field", "target_name": "density functional theory", "weight": 3.0, "year": 2018}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 20.0, "year": 2018}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 9.0, "year": 2018}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 3.0, "year": 2018}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2018}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 17.0, "year": 2018}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 12.0, "year": 2018}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2018}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2018}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 3.0, "year": 2018}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 18.0, "year": 2018}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2018}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2018}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 9.0, "year": 2018}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 4.0, "year": 2018}, {"source": "40", "target": "79", "source_name": "magnetic field", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 4.0, "year": 2018}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 12.0, "year": 2018}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 12.0, "year": 2018}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 6.0, "year": 2018}, {"source": "40", "target": "86", "source_name": "magnetic field", "target_name": "induction motor", "weight": 1.0, "year": 2018}, {"source": "40", "target": "87", "source_name": "magnetic field", "target_name": "charge transfer", "weight": 1.0, "year": 2018}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 13.0, "year": 2018}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 3.0, "year": 2018}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2018}, {"source": "41", "target": "46", "source_name": "grain boundaries", "target_name": "iron pnictides", "weight": 1.0, "year": 2018}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2018}, {"source": "41", "target": "54", "source_name": "grain boundaries", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2018}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 2.0, "year": 2018}, {"source": "41", "target": "79", "source_name": "grain boundaries", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 2.0, "year": 2018}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2018}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "42", "target": "68", "source_name": "rare earth", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2018}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2018}, {"source": "42", "target": "81", "source_name": "rare earth", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2018}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "43", "target": "68", "source_name": "transmission electron microscopy", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2018}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2018}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 6.0, "year": 2018}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2018}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 6.0, "year": 2018}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 4.0, "year": 2018}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2018}, {"source": "44", "target": "53", "source_name": "phase diagram", "target_name": "spectral weight", "weight": 1.0, "year": 2018}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2018}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 6.0, "year": 2018}, {"source": "44", "target": "57", "source_name": "phase diagram", "target_name": "density functional theory", "weight": 2.0, "year": 2018}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 10.0, "year": 2018}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 2.0, "year": 2018}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2018}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2018}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2018}, {"source": "44", "target": "66", "source_name": "phase diagram", "target_name": "sulfur hydride", "weight": 4.0, "year": 2018}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2018}, {"source": "44", "target": "69", "source_name": "phase diagram", "target_name": "selenium hydrides", "weight": 5.0, "year": 2018}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2018}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 2.0, "year": 2018}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2018}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2018}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2018}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 6.0, "year": 2018}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2018}, {"source": "44", "target": "92", "source_name": "phase diagram", "target_name": "ab initio", "weight": 1.0, "year": 2018}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2018}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2018}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "46", "target": "47", "source_name": "iron pnictides", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2018}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2018}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 2.0, "year": 2018}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2018}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2018}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2018}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2018}, {"source": "46", "target": "73", "source_name": "iron pnictides", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2018}, {"source": "46", "target": "90", "source_name": "iron pnictides", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 5.0, "year": 2018}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2018}, {"source": "47", "target": "66", "source_name": "magnetic susceptibility", "target_name": "sulfur hydride", "weight": 1.0, "year": 2018}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 4.0, "year": 2018}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 3.0, "year": 2018}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 4.0, "year": 2018}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "47", "target": "91", "source_name": "magnetic susceptibility", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 6.0, "year": 2018}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2018}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2018}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2018}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2018}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 6.0, "year": 2018}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2018}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 2.0, "year": 2018}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 10.0, "year": 2018}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 9.0, "year": 2018}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2018}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 2.0, "year": 2018}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2018}, {"source": "49", "target": "73", "source_name": "strongly correlated", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2018}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 5.0, "year": 2018}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2018}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2018}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2018}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2018}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2018}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2018}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2018}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2018}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 2.0, "year": 2018}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 2.0, "year": 2018}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2018}, {"source": "50", "target": "91", "source_name": "coated conductor", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 4.0, "year": 2018}, {"source": "51", "target": "86", "source_name": "wind turbine", "target_name": "induction motor", "weight": 1.0, "year": 2018}, {"source": "52", "target": "66", "source_name": "hydrogen sulfide", "target_name": "sulfur hydride", "weight": 1.0, "year": 2018}, {"source": "52", "target": "73", "source_name": "hydrogen sulfide", "target_name": "room temperature", "weight": 2.0, "year": 2018}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2018}, {"source": "53", "target": "55", "source_name": "spectral weight", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 3.0, "year": 2018}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 4.0, "year": 2018}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2018}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 7.0, "year": 2018}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 3.0, "year": 2018}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2018}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 2.0, "year": 2018}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2018}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2018}, {"source": "54", "target": "79", "source_name": "coherence length", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 5.0, "year": 2018}, {"source": "54", "target": "91", "source_name": "coherence length", "target_name": "heat capacity", "weight": 2.0, "year": 2018}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 2.0, "year": 2018}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2018}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2018}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 10.0, "year": 2018}, {"source": "56", "target": "60", "source_name": "hubbard model", "target_name": "mott insulator", "weight": 1.0, "year": 2018}, {"source": "56", "target": "65", "source_name": "hubbard model", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 3.0, "year": 2018}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2018}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 3.0, "year": 2018}, {"source": "57", "target": "69", "source_name": "density functional theory", "target_name": "selenium hydrides", "weight": 2.0, "year": 2018}, {"source": "57", "target": "73", "source_name": "density functional theory", "target_name": "room temperature", "weight": 3.0, "year": 2018}, {"source": "57", "target": "79", "source_name": "density functional theory", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "57", "target": "90", "source_name": "density functional theory", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "57", "target": "92", "source_name": "density functional theory", "target_name": "ab initio", "weight": 1.0, "year": 2018}, {"source": "58", "target": "62", "source_name": "single crystal", "target_name": "alternating current", "weight": 1.0, "year": 2018}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 4.0, "year": 2018}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2018}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2018}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 2.0, "year": 2018}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 4.0, "year": 2018}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2018}, {"source": "58", "target": "84", "source_name": "single crystal", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 5.0, "year": 2018}, {"source": "58", "target": "91", "source_name": "single crystal", "target_name": "heat capacity", "weight": 3.0, "year": 2018}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 5.0, "year": 2018}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 2.0, "year": 2018}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2018}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "61", "target": "64", "source_name": "synchronous motor", "target_name": "liquid helium", "weight": 1.0, "year": 2018}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 2.0, "year": 2018}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 2.0, "year": 2018}, {"source": "62", "target": "65", "source_name": "alternating current", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "62", "target": "77", "source_name": "alternating current", "target_name": "magnetic levitation", "weight": 1.0, "year": 2018}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "62", "target": "83", "source_name": "alternating current", "target_name": "permanent magnet", "weight": 1.0, "year": 2018}, {"source": "62", "target": "91", "source_name": "alternating current", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2018}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2018}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2018}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2018}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2018}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2018}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2018}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2018}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2018}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 2.0, "year": 2018}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2018}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2018}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2018}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2018}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 4.0, "year": 2018}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 3.0, "year": 2018}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2018}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2018}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 5.0, "year": 2018}, {"source": "65", "target": "91", "source_name": "copper oxide", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "66", "target": "69", "source_name": "sulfur hydride", "target_name": "selenium hydrides", "weight": 4.0, "year": 2018}, {"source": "66", "target": "70", "source_name": "sulfur hydride", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "66", "target": "73", "source_name": "sulfur hydride", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "66", "target": "79", "source_name": "sulfur hydride", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2018}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2018}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2018}, {"source": "67", "target": "88", "source_name": "magnesium diboride", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2018}, {"source": "68", "target": "79", "source_name": "nuclear magnetic resonance", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "68", "target": "81", "source_name": "nuclear magnetic resonance", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 3.0, "year": 2018}, {"source": "70", "target": "79", "source_name": "meissner effect", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2018}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 3.0, "year": 2018}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2018}, {"source": "71", "target": "73", "source_name": "van hove", "target_name": "room temperature", "weight": 1.0, "year": 2018}, {"source": "72", "target": "73", "source_name": "electrical resistance", "target_name": "room temperature", "weight": 4.0, "year": 2018}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 3.0, "year": 2018}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2018}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2018}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2018}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2018}, {"source": "73", "target": "79", "source_name": "room temperature", "target_name": "crystal structure", "weight": 1.0, "year": 2018}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2018}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2018}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2018}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 5.0, "year": 2018}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2018}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2018}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2018}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 6.0, "year": 2018}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2018}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2018}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2018}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "79", "target": "84", "source_name": "crystal structure", "target_name": "ground state", "weight": 2.0, "year": 2018}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2018}, {"source": "79", "target": "90", "source_name": "crystal structure", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "79", "target": "91", "source_name": "crystal structure", "target_name": "heat capacity", "weight": 2.0, "year": 2018}, {"source": "79", "target": "92", "source_name": "crystal structure", "target_name": "ab initio", "weight": 2.0, "year": 2018}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2018}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 2.0, "year": 2018}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 2.0, "year": 2018}, {"source": "81", "target": "88", "source_name": "finite element", "target_name": "energy storage", "weight": 1.0, "year": 2018}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 3.0, "year": 2018}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2018}, {"source": "87", "target": "90", "source_name": "charge transfer", "target_name": "cooper pair", "weight": 4.0, "year": 2018}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2018}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2018}]}, {"2019": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2019}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2019}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2019}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2019}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 3.0, "year": 2019}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2019}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2019}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 24.0, "year": 2019}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2019}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 3.0, "year": 2019}, {"source": "1", "target": "5", "source_name": "critical temperature", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2019}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 2.0, "year": 2019}, {"source": "1", "target": "9", "source_name": "critical temperature", "target_name": "condensed matter physics", "weight": 2.0, "year": 2019}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 12.0, "year": 2019}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2019}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 2.0, "year": 2019}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2019}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 2.0, "year": 2019}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2019}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 10.0, "year": 2019}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2019}, {"source": "1", "target": "18", "source_name": "critical temperature", "target_name": "fermi arcs", "weight": 5.0, "year": 2019}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 7.0, "year": 2019}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 16.0, "year": 2019}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 4.0, "year": 2019}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 3.0, "year": 2019}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 7.0, "year": 2019}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2019}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 11.0, "year": 2019}, {"source": "1", "target": "29", "source_name": "critical temperature", "target_name": "raman scattering", "weight": 2.0, "year": 2019}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 9.0, "year": 2019}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2019}, {"source": "1", "target": "33", "source_name": "critical temperature", "target_name": "strontium titanate", "weight": 4.0, "year": 2019}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 10.0, "year": 2019}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 4.0, "year": 2019}, {"source": "1", "target": "36", "source_name": "critical temperature", "target_name": "ion beam", "weight": 1.0, "year": 2019}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 8.0, "year": 2019}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 2.0, "year": 2019}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 34.0, "year": 2019}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 4.0, "year": 2019}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 3.0, "year": 2019}, {"source": "1", "target": "43", "source_name": "critical temperature", "target_name": "transmission electron microscopy", "weight": 5.0, "year": 2019}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 12.0, "year": 2019}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 4.0, "year": 2019}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 10.0, "year": 2019}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 11.0, "year": 2019}, {"source": "1", "target": "52", "source_name": "critical temperature", "target_name": "hydrogen sulfide", "weight": 4.0, "year": 2019}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 7.0, "year": 2019}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 2.0, "year": 2019}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 7.0, "year": 2019}, {"source": "1", "target": "57", "source_name": "critical temperature", "target_name": "density functional theory", "weight": 7.0, "year": 2019}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 14.0, "year": 2019}, {"source": "1", "target": "59", "source_name": "critical temperature", "target_name": "monte carlo", "weight": 3.0, "year": 2019}, {"source": "1", "target": "60", "source_name": "critical temperature", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2019}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 24.0, "year": 2019}, {"source": "1", "target": "66", "source_name": "critical temperature", "target_name": "sulfur hydride", "weight": 7.0, "year": 2019}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2019}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 6.0, "year": 2019}, {"source": "1", "target": "69", "source_name": "critical temperature", "target_name": "selenium hydrides", "weight": 2.0, "year": 2019}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 4.0, "year": 2019}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2019}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 7.0, "year": 2019}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 16.0, "year": 2019}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2019}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 4.0, "year": 2019}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 7.0, "year": 2019}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 6.0, "year": 2019}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2019}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2019}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 4.0, "year": 2019}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 3.0, "year": 2019}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 15.0, "year": 2019}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 6.0, "year": 2019}, {"source": "2", "target": "4", "source_name": "current density", "target_name": "penetration depth", "weight": 1.0, "year": 2019}, {"source": "2", "target": "5", "source_name": "current density", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2019}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2019}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2019}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 9.0, "year": 2019}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2019}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2019}, {"source": "2", "target": "14", "source_name": "current density", "target_name": "iron selenide", "weight": 1.0, "year": 2019}, {"source": "2", "target": "15", "source_name": "current density", "target_name": "magnetic flux", "weight": 2.0, "year": 2019}, {"source": "2", "target": "17", "source_name": "current density", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2019}, {"source": "2", "target": "18", "source_name": "current density", "target_name": "fermi arcs", "weight": 5.0, "year": 2019}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2019}, {"source": "2", "target": "20", "source_name": "current density", "target_name": "specific heat", "weight": 6.0, "year": 2019}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 3.0, "year": 2019}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2019}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2019}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 3.0, "year": 2019}, {"source": "2", "target": "28", "source_name": "current density", "target_name": "bcs theory", "weight": 1.0, "year": 2019}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2019}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2019}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 2.0, "year": 2019}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2019}, {"source": "2", "target": "39", "source_name": "current density", "target_name": "finite element method", "weight": 1.0, "year": 2019}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 43.0, "year": 2019}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 4.0, "year": 2019}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2019}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "2", "target": "45", "source_name": "current density", "target_name": "power transmission", "weight": 1.0, "year": 2019}, {"source": "2", "target": "47", "source_name": "current density", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 6.0, "year": 2019}, {"source": "2", "target": "51", "source_name": "current density", "target_name": "wind turbine", "weight": 1.0, "year": 2019}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 2.0, "year": 2019}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 6.0, "year": 2019}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 3.0, "year": 2019}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 2.0, "year": 2019}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2019}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 3.0, "year": 2019}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 8.0, "year": 2019}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2019}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2019}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 3.0, "year": 2019}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 8.0, "year": 2019}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2019}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 6.0, "year": 2019}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2019}, {"source": "2", "target": "79", "source_name": "current density", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "2", "target": "80", "source_name": "current density", "target_name": "quench propagation", "weight": 1.0, "year": 2019}, {"source": "2", "target": "81", "source_name": "current density", "target_name": "finite element", "weight": 2.0, "year": 2019}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2019}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 5.0, "year": 2019}, {"source": "2", "target": "86", "source_name": "current density", "target_name": "induction motor", "weight": 1.0, "year": 2019}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 4.0, "year": 2019}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 2.0, "year": 2019}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 2.0, "year": 2019}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2019}, {"source": "3", "target": "23", "source_name": "charge density waves", "target_name": "order parameter", "weight": 1.0, "year": 2019}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 2.0, "year": 2019}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2019}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2019}, {"source": "3", "target": "44", "source_name": "charge density waves", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "3", "target": "73", "source_name": "charge density waves", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "4", "target": "14", "source_name": "penetration depth", "target_name": "iron selenide", "weight": 1.0, "year": 2019}, {"source": "4", "target": "17", "source_name": "penetration depth", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2019}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2019}, {"source": "4", "target": "20", "source_name": "penetration depth", "target_name": "specific heat", "weight": 1.0, "year": 2019}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2019}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 2.0, "year": 2019}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 4.0, "year": 2019}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2019}, {"source": "4", "target": "55", "source_name": "penetration depth", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 2.0, "year": 2019}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2019}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "5", "target": "23", "source_name": "chemical vapor deposition", "target_name": "order parameter", "weight": 1.0, "year": 2019}, {"source": "5", "target": "36", "source_name": "chemical vapor deposition", "target_name": "ion beam", "weight": 1.0, "year": 2019}, {"source": "5", "target": "40", "source_name": "chemical vapor deposition", "target_name": "magnetic field", "weight": 1.0, "year": 2019}, {"source": "5", "target": "88", "source_name": "chemical vapor deposition", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 2.0, "year": 2019}, {"source": "6", "target": "10", "source_name": "brillouin zone", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2019}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 2.0, "year": 2019}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2019}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 4.0, "year": 2019}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 2.0, "year": 2019}, {"source": "6", "target": "34", "source_name": "brillouin zone", "target_name": "exchange interaction", "weight": 1.0, "year": 2019}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 6.0, "year": 2019}, {"source": "6", "target": "44", "source_name": "brillouin zone", "target_name": "phase diagram", "weight": 4.0, "year": 2019}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2019}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 4.0, "year": 2019}, {"source": "6", "target": "57", "source_name": "brillouin zone", "target_name": "density functional theory", "weight": 1.0, "year": 2019}, {"source": "6", "target": "79", "source_name": "brillouin zone", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 3.0, "year": 2019}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 4.0, "year": 2019}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2019}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2019}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2019}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2019}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2019}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 5.0, "year": 2019}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2019}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2019}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 4.0, "year": 2019}, {"source": "7", "target": "59", "source_name": "kinetic energy", "target_name": "monte carlo", "weight": 1.0, "year": 2019}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2019}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2019}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "8", "target": "22", "source_name": "symmetry breaking", "target_name": "unit cell", "weight": 1.0, "year": 2019}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2019}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2019}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "9", "target": "10", "source_name": "condensed matter physics", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2019}, {"source": "9", "target": "17", "source_name": "condensed matter physics", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2019}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 3.0, "year": 2019}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2019}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2019}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 24.0, "year": 2019}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 2.0, "year": 2019}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2019}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2019}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2019}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2019}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2019}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "9", "target": "58", "source_name": "condensed matter physics", "target_name": "single crystal", "weight": 1.0, "year": 2019}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2019}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 3.0, "year": 2019}, {"source": "9", "target": "73", "source_name": "condensed matter physics", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2019}, {"source": "9", "target": "87", "source_name": "condensed matter physics", "target_name": "charge transfer", "weight": 4.0, "year": 2019}, {"source": "9", "target": "90", "source_name": "condensed matter physics", "target_name": "cooper pair", "weight": 4.0, "year": 2019}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2019}, {"source": "10", "target": "13", "source_name": "liquid nitrogen", "target_name": "josephson junctions", "weight": 1.0, "year": 2019}, {"source": "10", "target": "14", "source_name": "liquid nitrogen", "target_name": "iron selenide", "weight": 1.0, "year": 2019}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2019}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 2.0, "year": 2019}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2019}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2019}, {"source": "10", "target": "22", "source_name": "liquid nitrogen", "target_name": "unit cell", "weight": 2.0, "year": 2019}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2019}, {"source": "10", "target": "27", "source_name": "liquid nitrogen", "target_name": "ac losses", "weight": 1.0, "year": 2019}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2019}, {"source": "10", "target": "31", "source_name": "liquid nitrogen", "target_name": "condensed matter", "weight": 1.0, "year": 2019}, {"source": "10", "target": "33", "source_name": "liquid nitrogen", "target_name": "strontium titanate", "weight": 1.0, "year": 2019}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 2.0, "year": 2019}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 2.0, "year": 2019}, {"source": "10", "target": "39", "source_name": "liquid nitrogen", "target_name": "finite element method", "weight": 1.0, "year": 2019}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 21.0, "year": 2019}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2019}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 2.0, "year": 2019}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2019}, {"source": "10", "target": "44", "source_name": "liquid nitrogen", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 5.0, "year": 2019}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2019}, {"source": "10", "target": "51", "source_name": "liquid nitrogen", "target_name": "wind turbine", "weight": 1.0, "year": 2019}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 3.0, "year": 2019}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2019}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2019}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2019}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2019}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2019}, {"source": "10", "target": "66", "source_name": "liquid nitrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2019}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2019}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2019}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 2.0, "year": 2019}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 5.0, "year": 2019}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2019}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2019}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2019}, {"source": "10", "target": "79", "source_name": "liquid nitrogen", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "10", "target": "80", "source_name": "liquid nitrogen", "target_name": "quench propagation", "weight": 1.0, "year": 2019}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 2.0, "year": 2019}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 3.0, "year": 2019}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2019}, {"source": "10", "target": "86", "source_name": "liquid nitrogen", "target_name": "induction motor", "weight": 1.0, "year": 2019}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 5.0, "year": 2019}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 2.0, "year": 2019}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "10", "target": "92", "source_name": "liquid nitrogen", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "11", "target": "13", "source_name": "yttrium barium copper oxide", "target_name": "josephson junctions", "weight": 1.0, "year": 2019}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2019}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 3.0, "year": 2019}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2019}, {"source": "11", "target": "51", "source_name": "yttrium barium copper oxide", "target_name": "wind turbine", "weight": 1.0, "year": 2019}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2019}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 9.0, "year": 2019}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2019}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 6.0, "year": 2019}, {"source": "12", "target": "19", "source_name": "scanning tunneling microscopy", "target_name": "electric field", "weight": 2.0, "year": 2019}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2019}, {"source": "12", "target": "22", "source_name": "scanning tunneling microscopy", "target_name": "unit cell", "weight": 5.0, "year": 2019}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 6.0, "year": 2019}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2019}, {"source": "12", "target": "58", "source_name": "scanning tunneling microscopy", "target_name": "single crystal", "weight": 3.0, "year": 2019}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2019}, {"source": "12", "target": "60", "source_name": "scanning tunneling microscopy", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "12", "target": "87", "source_name": "scanning tunneling microscopy", "target_name": "charge transfer", "weight": 3.0, "year": 2019}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2019}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2019}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2019}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 3.0, "year": 2019}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2019}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2019}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 2.0, "year": 2019}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2019}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2019}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2019}, {"source": "13", "target": "65", "source_name": "josephson junctions", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2019}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "14", "target": "20", "source_name": "iron selenide", "target_name": "specific heat", "weight": 1.0, "year": 2019}, {"source": "14", "target": "22", "source_name": "iron selenide", "target_name": "unit cell", "weight": 1.0, "year": 2019}, {"source": "14", "target": "28", "source_name": "iron selenide", "target_name": "bcs theory", "weight": 1.0, "year": 2019}, {"source": "14", "target": "33", "source_name": "iron selenide", "target_name": "strontium titanate", "weight": 3.0, "year": 2019}, {"source": "14", "target": "40", "source_name": "iron selenide", "target_name": "magnetic field", "weight": 1.0, "year": 2019}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2019}, {"source": "15", "target": "20", "source_name": "magnetic flux", "target_name": "specific heat", "weight": 1.0, "year": 2019}, {"source": "15", "target": "23", "source_name": "magnetic flux", "target_name": "order parameter", "weight": 1.0, "year": 2019}, {"source": "15", "target": "32", "source_name": "magnetic flux", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2019}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2019}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 11.0, "year": 2019}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 3.0, "year": 2019}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 2.0, "year": 2019}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 3.0, "year": 2019}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2019}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "15", "target": "83", "source_name": "magnetic flux", "target_name": "permanent magnet", "weight": 1.0, "year": 2019}, {"source": "15", "target": "88", "source_name": "magnetic flux", "target_name": "energy storage", "weight": 2.0, "year": 2019}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 2.0, "year": 2019}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2019}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2019}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 1.0, "year": 2019}, {"source": "16", "target": "34", "source_name": "coulomb repulsion", "target_name": "exchange interaction", "weight": 4.0, "year": 2019}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 2.0, "year": 2019}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 2.0, "year": 2019}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 7.0, "year": 2019}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 6.0, "year": 2019}, {"source": "16", "target": "59", "source_name": "coulomb repulsion", "target_name": "monte carlo", "weight": 3.0, "year": 2019}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "16", "target": "72", "source_name": "coulomb repulsion", "target_name": "electrical resistance", "weight": 1.0, "year": 2019}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2019}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2019}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 2.0, "year": 2019}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "17", "target": "19", "source_name": "molecular beam epitaxy", "target_name": "electric field", "weight": 3.0, "year": 2019}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 5.0, "year": 2019}, {"source": "17", "target": "31", "source_name": "molecular beam epitaxy", "target_name": "condensed matter", "weight": 4.0, "year": 2019}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 8.0, "year": 2019}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2019}, {"source": "17", "target": "54", "source_name": "molecular beam epitaxy", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 4.0, "year": 2019}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 3.0, "year": 2019}, {"source": "17", "target": "70", "source_name": "molecular beam epitaxy", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 2.0, "year": 2019}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 6.0, "year": 2019}, {"source": "17", "target": "90", "source_name": "molecular beam epitaxy", "target_name": "cooper pair", "weight": 5.0, "year": 2019}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 7.0, "year": 2019}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2019}, {"source": "18", "target": "30", "source_name": "fermi arcs", "target_name": "fermi level", "weight": 1.0, "year": 2019}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2019}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 7.0, "year": 2019}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2019}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 7.0, "year": 2019}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2019}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2019}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 11.0, "year": 2019}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "19", "target": "50", "source_name": "electric field", "target_name": "coated conductor", "weight": 1.0, "year": 2019}, {"source": "19", "target": "58", "source_name": "electric field", "target_name": "single crystal", "weight": 1.0, "year": 2019}, {"source": "19", "target": "65", "source_name": "electric field", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 3.0, "year": 2019}, {"source": "19", "target": "87", "source_name": "electric field", "target_name": "charge transfer", "weight": 1.0, "year": 2019}, {"source": "19", "target": "91", "source_name": "electric field", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "20", "target": "22", "source_name": "specific heat", "target_name": "unit cell", "weight": 1.0, "year": 2019}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 3.0, "year": 2019}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 4.0, "year": 2019}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 8.0, "year": 2019}, {"source": "20", "target": "35", "source_name": "specific heat", "target_name": "space group", "weight": 3.0, "year": 2019}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 3.0, "year": 2019}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 12.0, "year": 2019}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2019}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2019}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 6.0, "year": 2019}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2019}, {"source": "20", "target": "54", "source_name": "specific heat", "target_name": "coherence length", "weight": 2.0, "year": 2019}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2019}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 9.0, "year": 2019}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 7.0, "year": 2019}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2019}, {"source": "20", "target": "79", "source_name": "specific heat", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2019}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 2.0, "year": 2019}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 5.0, "year": 2019}, {"source": "20", "target": "92", "source_name": "specific heat", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 3.0, "year": 2019}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2019}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "21", "target": "46", "source_name": "grain boundary", "target_name": "iron pnictides", "weight": 1.0, "year": 2019}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2019}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "22", "target": "28", "source_name": "unit cell", "target_name": "bcs theory", "weight": 1.0, "year": 2019}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 3.0, "year": 2019}, {"source": "22", "target": "33", "source_name": "unit cell", "target_name": "strontium titanate", "weight": 1.0, "year": 2019}, {"source": "22", "target": "37", "source_name": "unit cell", "target_name": "fermi surface", "weight": 1.0, "year": 2019}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 4.0, "year": 2019}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "22", "target": "49", "source_name": "unit cell", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 2.0, "year": 2019}, {"source": "22", "target": "57", "source_name": "unit cell", "target_name": "density functional theory", "weight": 3.0, "year": 2019}, {"source": "22", "target": "58", "source_name": "unit cell", "target_name": "single crystal", "weight": 3.0, "year": 2019}, {"source": "22", "target": "65", "source_name": "unit cell", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "22", "target": "70", "source_name": "unit cell", "target_name": "meissner effect", "weight": 2.0, "year": 2019}, {"source": "22", "target": "73", "source_name": "unit cell", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "22", "target": "87", "source_name": "unit cell", "target_name": "charge transfer", "weight": 2.0, "year": 2019}, {"source": "23", "target": "26", "source_name": "order parameter", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2019}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2019}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2019}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2019}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 8.0, "year": 2019}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 2.0, "year": 2019}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 4.0, "year": 2019}, {"source": "23", "target": "41", "source_name": "order parameter", "target_name": "grain boundaries", "weight": 1.0, "year": 2019}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 4.0, "year": 2019}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2019}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2019}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2019}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 3.0, "year": 2019}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2019}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 3.0, "year": 2019}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2019}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2019}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2019}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2019}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2019}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2019}, {"source": "23", "target": "73", "source_name": "order parameter", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2019}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2019}, {"source": "23", "target": "88", "source_name": "order parameter", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 6.0, "year": 2019}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 4.0, "year": 2019}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2019}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 2.0, "year": 2019}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "24", "target": "64", "source_name": "magnetic resonance imaging", "target_name": "liquid helium", "weight": 1.0, "year": 2019}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2019}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2019}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 3.0, "year": 2019}, {"source": "24", "target": "88", "source_name": "magnetic resonance imaging", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "26", "target": "30", "source_name": "carbon nanotubes", "target_name": "fermi level", "weight": 1.0, "year": 2019}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2019}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "26", "target": "71", "source_name": "carbon nanotubes", "target_name": "van hove", "weight": 1.0, "year": 2019}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 2.0, "year": 2019}, {"source": "26", "target": "90", "source_name": "carbon nanotubes", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "27", "target": "39", "source_name": "ac losses", "target_name": "finite element method", "weight": 1.0, "year": 2019}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 5.0, "year": 2019}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2019}, {"source": "27", "target": "45", "source_name": "ac losses", "target_name": "power transmission", "weight": 1.0, "year": 2019}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2019}, {"source": "27", "target": "51", "source_name": "ac losses", "target_name": "wind turbine", "weight": 1.0, "year": 2019}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2019}, {"source": "27", "target": "62", "source_name": "ac losses", "target_name": "alternating current", "weight": 1.0, "year": 2019}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2019}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2019}, {"source": "27", "target": "81", "source_name": "ac losses", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "27", "target": "86", "source_name": "ac losses", "target_name": "induction motor", "weight": 1.0, "year": 2019}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 2.0, "year": 2019}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2019}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 3.0, "year": 2019}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2019}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 5.0, "year": 2019}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2019}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2019}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2019}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2019}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2019}, {"source": "28", "target": "58", "source_name": "bcs theory", "target_name": "single crystal", "weight": 1.0, "year": 2019}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 3.0, "year": 2019}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2019}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2019}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2019}, {"source": "28", "target": "79", "source_name": "bcs theory", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2019}, {"source": "28", "target": "92", "source_name": "bcs theory", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2019}, {"source": "29", "target": "40", "source_name": "raman scattering", "target_name": "magnetic field", "weight": 1.0, "year": 2019}, {"source": "29", "target": "44", "source_name": "raman scattering", "target_name": "phase diagram", "weight": 2.0, "year": 2019}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2019}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2019}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 4.0, "year": 2019}, {"source": "29", "target": "70", "source_name": "raman scattering", "target_name": "meissner effect", "weight": 2.0, "year": 2019}, {"source": "29", "target": "87", "source_name": "raman scattering", "target_name": "charge transfer", "weight": 1.0, "year": 2019}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2019}, {"source": "30", "target": "35", "source_name": "fermi level", "target_name": "space group", "weight": 1.0, "year": 2019}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 3.0, "year": 2019}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2019}, {"source": "30", "target": "47", "source_name": "fermi level", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "30", "target": "54", "source_name": "fermi level", "target_name": "coherence length", "weight": 2.0, "year": 2019}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 2.0, "year": 2019}, {"source": "30", "target": "58", "source_name": "fermi level", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "30", "target": "60", "source_name": "fermi level", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "30", "target": "65", "source_name": "fermi level", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 3.0, "year": 2019}, {"source": "30", "target": "72", "source_name": "fermi level", "target_name": "electrical resistance", "weight": 1.0, "year": 2019}, {"source": "30", "target": "73", "source_name": "fermi level", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "30", "target": "79", "source_name": "fermi level", "target_name": "crystal structure", "weight": 3.0, "year": 2019}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "30", "target": "91", "source_name": "fermi level", "target_name": "heat capacity", "weight": 3.0, "year": 2019}, {"source": "30", "target": "92", "source_name": "fermi level", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "31", "target": "37", "source_name": "condensed matter", "target_name": "fermi surface", "weight": 1.0, "year": 2019}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2019}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2019}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2019}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 2.0, "year": 2019}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2019}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "31", "target": "58", "source_name": "condensed matter", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2019}, {"source": "31", "target": "62", "source_name": "condensed matter", "target_name": "alternating current", "weight": 1.0, "year": 2019}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2019}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 3.0, "year": 2019}, {"source": "31", "target": "73", "source_name": "condensed matter", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2019}, {"source": "31", "target": "87", "source_name": "condensed matter", "target_name": "charge transfer", "weight": 4.0, "year": 2019}, {"source": "31", "target": "90", "source_name": "condensed matter", "target_name": "cooper pair", "weight": 4.0, "year": 2019}, {"source": "31", "target": "91", "source_name": "condensed matter", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2019}, {"source": "32", "target": "61", "source_name": "flywheel energy storage", "target_name": "synchronous motor", "weight": 1.0, "year": 2019}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2019}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 4.0, "year": 2019}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 10.0, "year": 2019}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 1.0, "year": 2019}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 4.0, "year": 2019}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2019}, {"source": "34", "target": "49", "source_name": "exchange interaction", "target_name": "strongly correlated", "weight": 4.0, "year": 2019}, {"source": "34", "target": "56", "source_name": "exchange interaction", "target_name": "hubbard model", "weight": 3.0, "year": 2019}, {"source": "34", "target": "57", "source_name": "exchange interaction", "target_name": "density functional theory", "weight": 1.0, "year": 2019}, {"source": "34", "target": "59", "source_name": "exchange interaction", "target_name": "monte carlo", "weight": 3.0, "year": 2019}, {"source": "34", "target": "66", "source_name": "exchange interaction", "target_name": "sulfur hydride", "weight": 2.0, "year": 2019}, {"source": "34", "target": "72", "source_name": "exchange interaction", "target_name": "electrical resistance", "weight": 1.0, "year": 2019}, {"source": "34", "target": "79", "source_name": "exchange interaction", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 2.0, "year": 2019}, {"source": "35", "target": "40", "source_name": "space group", "target_name": "magnetic field", "weight": 1.0, "year": 2019}, {"source": "35", "target": "47", "source_name": "space group", "target_name": "magnetic susceptibility", "weight": 3.0, "year": 2019}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 3.0, "year": 2019}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2019}, {"source": "35", "target": "91", "source_name": "space group", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "35", "target": "92", "source_name": "space group", "target_name": "ab initio", "weight": 2.0, "year": 2019}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2019}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2019}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2019}, {"source": "36", "target": "54", "source_name": "ion beam", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2019}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2019}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 2.0, "year": 2019}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 4.0, "year": 2019}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2019}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2019}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2019}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 4.0, "year": 2019}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2019}, {"source": "37", "target": "57", "source_name": "fermi surface", "target_name": "density functional theory", "weight": 2.0, "year": 2019}, {"source": "37", "target": "58", "source_name": "fermi surface", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2019}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2019}, {"source": "37", "target": "68", "source_name": "fermi surface", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2019}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 5.0, "year": 2019}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 8.0, "year": 2019}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2019}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2019}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 8.0, "year": 2019}, {"source": "37", "target": "91", "source_name": "fermi surface", "target_name": "heat capacity", "weight": 2.0, "year": 2019}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "38", "target": "66", "source_name": "metallic hydrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2019}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "38", "target": "79", "source_name": "metallic hydrogen", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2019}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 3.0, "year": 2019}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 11.0, "year": 2019}, {"source": "39", "target": "42", "source_name": "finite element method", "target_name": "rare earth", "weight": 1.0, "year": 2019}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2019}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 2.0, "year": 2019}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 2.0, "year": 2019}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "39", "target": "68", "source_name": "finite element method", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2019}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2019}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 15.0, "year": 2019}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 2.0, "year": 2019}, {"source": "39", "target": "86", "source_name": "finite element method", "target_name": "induction motor", "weight": 1.0, "year": 2019}, {"source": "39", "target": "88", "source_name": "finite element method", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 4.0, "year": 2019}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 4.0, "year": 2019}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 11.0, "year": 2019}, {"source": "40", "target": "46", "source_name": "magnetic field", "target_name": "iron pnictides", "weight": 1.0, "year": 2019}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 10.0, "year": 2019}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2019}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 14.0, "year": 2019}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 4.0, "year": 2019}, {"source": "40", "target": "52", "source_name": "magnetic field", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2019}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2019}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2019}, {"source": "40", "target": "57", "source_name": "magnetic field", "target_name": "density functional theory", "weight": 3.0, "year": 2019}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 23.0, "year": 2019}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 9.0, "year": 2019}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 3.0, "year": 2019}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2019}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 17.0, "year": 2019}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 13.0, "year": 2019}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2019}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 3.0, "year": 2019}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 4.0, "year": 2019}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 19.0, "year": 2019}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2019}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2019}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 10.0, "year": 2019}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 4.0, "year": 2019}, {"source": "40", "target": "79", "source_name": "magnetic field", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 4.0, "year": 2019}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 12.0, "year": 2019}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 12.0, "year": 2019}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 6.0, "year": 2019}, {"source": "40", "target": "86", "source_name": "magnetic field", "target_name": "induction motor", "weight": 1.0, "year": 2019}, {"source": "40", "target": "87", "source_name": "magnetic field", "target_name": "charge transfer", "weight": 1.0, "year": 2019}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 13.0, "year": 2019}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 4.0, "year": 2019}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2019}, {"source": "41", "target": "46", "source_name": "grain boundaries", "target_name": "iron pnictides", "weight": 1.0, "year": 2019}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2019}, {"source": "41", "target": "54", "source_name": "grain boundaries", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2019}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 2.0, "year": 2019}, {"source": "41", "target": "79", "source_name": "grain boundaries", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 3.0, "year": 2019}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2019}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "42", "target": "68", "source_name": "rare earth", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2019}, {"source": "42", "target": "73", "source_name": "rare earth", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2019}, {"source": "42", "target": "79", "source_name": "rare earth", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "42", "target": "81", "source_name": "rare earth", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2019}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "42", "target": "92", "source_name": "rare earth", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "43", "target": "68", "source_name": "transmission electron microscopy", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2019}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2019}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 6.0, "year": 2019}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 5.0, "year": 2019}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 6.0, "year": 2019}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 5.0, "year": 2019}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2019}, {"source": "44", "target": "53", "source_name": "phase diagram", "target_name": "spectral weight", "weight": 1.0, "year": 2019}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2019}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 3.0, "year": 2019}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 6.0, "year": 2019}, {"source": "44", "target": "57", "source_name": "phase diagram", "target_name": "density functional theory", "weight": 2.0, "year": 2019}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 11.0, "year": 2019}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 2.0, "year": 2019}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2019}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2019}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2019}, {"source": "44", "target": "66", "source_name": "phase diagram", "target_name": "sulfur hydride", "weight": 4.0, "year": 2019}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2019}, {"source": "44", "target": "69", "source_name": "phase diagram", "target_name": "selenium hydrides", "weight": 5.0, "year": 2019}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2019}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 5.0, "year": 2019}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2019}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2019}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 3.0, "year": 2019}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2019}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 6.0, "year": 2019}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2019}, {"source": "44", "target": "92", "source_name": "phase diagram", "target_name": "ab initio", "weight": 2.0, "year": 2019}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2019}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2019}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "46", "target": "47", "source_name": "iron pnictides", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2019}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2019}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 2.0, "year": 2019}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2019}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2019}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2019}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2019}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2019}, {"source": "46", "target": "73", "source_name": "iron pnictides", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2019}, {"source": "46", "target": "90", "source_name": "iron pnictides", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "47", "target": "49", "source_name": "magnetic susceptibility", "target_name": "strongly correlated", "weight": 1.0, "year": 2019}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 2.0, "year": 2019}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 6.0, "year": 2019}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2019}, {"source": "47", "target": "66", "source_name": "magnetic susceptibility", "target_name": "sulfur hydride", "weight": 3.0, "year": 2019}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 5.0, "year": 2019}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 4.0, "year": 2019}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 4.0, "year": 2019}, {"source": "47", "target": "87", "source_name": "magnetic susceptibility", "target_name": "charge transfer", "weight": 1.0, "year": 2019}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 2.0, "year": 2019}, {"source": "47", "target": "91", "source_name": "magnetic susceptibility", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 6.0, "year": 2019}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2019}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2019}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2019}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2019}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 6.0, "year": 2019}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2019}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 4.0, "year": 2019}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 10.0, "year": 2019}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 11.0, "year": 2019}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2019}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 3.0, "year": 2019}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2019}, {"source": "49", "target": "73", "source_name": "strongly correlated", "target_name": "room temperature", "weight": 3.0, "year": 2019}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2019}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 7.0, "year": 2019}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2019}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2019}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2019}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2019}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2019}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2019}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2019}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 2.0, "year": 2019}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 2.0, "year": 2019}, {"source": "50", "target": "88", "source_name": "coated conductor", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2019}, {"source": "50", "target": "91", "source_name": "coated conductor", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 4.0, "year": 2019}, {"source": "51", "target": "86", "source_name": "wind turbine", "target_name": "induction motor", "weight": 1.0, "year": 2019}, {"source": "52", "target": "66", "source_name": "hydrogen sulfide", "target_name": "sulfur hydride", "weight": 1.0, "year": 2019}, {"source": "52", "target": "73", "source_name": "hydrogen sulfide", "target_name": "room temperature", "weight": 2.0, "year": 2019}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2019}, {"source": "53", "target": "55", "source_name": "spectral weight", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 3.0, "year": 2019}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 4.0, "year": 2019}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2019}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 7.0, "year": 2019}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 3.0, "year": 2019}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2019}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 2.0, "year": 2019}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2019}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2019}, {"source": "54", "target": "79", "source_name": "coherence length", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 5.0, "year": 2019}, {"source": "54", "target": "91", "source_name": "coherence length", "target_name": "heat capacity", "weight": 2.0, "year": 2019}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 2.0, "year": 2019}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 3.0, "year": 2019}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2019}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2019}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 10.0, "year": 2019}, {"source": "56", "target": "60", "source_name": "hubbard model", "target_name": "mott insulator", "weight": 1.0, "year": 2019}, {"source": "56", "target": "65", "source_name": "hubbard model", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 3.0, "year": 2019}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2019}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 3.0, "year": 2019}, {"source": "57", "target": "69", "source_name": "density functional theory", "target_name": "selenium hydrides", "weight": 2.0, "year": 2019}, {"source": "57", "target": "73", "source_name": "density functional theory", "target_name": "room temperature", "weight": 3.0, "year": 2019}, {"source": "57", "target": "79", "source_name": "density functional theory", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "57", "target": "90", "source_name": "density functional theory", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "57", "target": "92", "source_name": "density functional theory", "target_name": "ab initio", "weight": 2.0, "year": 2019}, {"source": "58", "target": "62", "source_name": "single crystal", "target_name": "alternating current", "weight": 1.0, "year": 2019}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 4.0, "year": 2019}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2019}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2019}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 2.0, "year": 2019}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 4.0, "year": 2019}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2019}, {"source": "58", "target": "84", "source_name": "single crystal", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 5.0, "year": 2019}, {"source": "58", "target": "91", "source_name": "single crystal", "target_name": "heat capacity", "weight": 3.0, "year": 2019}, {"source": "59", "target": "73", "source_name": "monte carlo", "target_name": "room temperature", "weight": 2.0, "year": 2019}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 7.0, "year": 2019}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 2.0, "year": 2019}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2019}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2019}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "61", "target": "64", "source_name": "synchronous motor", "target_name": "liquid helium", "weight": 1.0, "year": 2019}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 2.0, "year": 2019}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 3.0, "year": 2019}, {"source": "61", "target": "88", "source_name": "synchronous motor", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "62", "target": "65", "source_name": "alternating current", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "62", "target": "77", "source_name": "alternating current", "target_name": "magnetic levitation", "weight": 1.0, "year": 2019}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "62", "target": "83", "source_name": "alternating current", "target_name": "permanent magnet", "weight": 1.0, "year": 2019}, {"source": "62", "target": "91", "source_name": "alternating current", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2019}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2019}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2019}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2019}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2019}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2019}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2019}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2019}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2019}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 2.0, "year": 2019}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2019}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2019}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2019}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2019}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 4.0, "year": 2019}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 3.0, "year": 2019}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2019}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2019}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 5.0, "year": 2019}, {"source": "65", "target": "91", "source_name": "copper oxide", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "66", "target": "69", "source_name": "sulfur hydride", "target_name": "selenium hydrides", "weight": 4.0, "year": 2019}, {"source": "66", "target": "70", "source_name": "sulfur hydride", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "66", "target": "73", "source_name": "sulfur hydride", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "66", "target": "79", "source_name": "sulfur hydride", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2019}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2019}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2019}, {"source": "67", "target": "88", "source_name": "magnesium diboride", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2019}, {"source": "68", "target": "77", "source_name": "nuclear magnetic resonance", "target_name": "magnetic levitation", "weight": 1.0, "year": 2019}, {"source": "68", "target": "79", "source_name": "nuclear magnetic resonance", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "68", "target": "81", "source_name": "nuclear magnetic resonance", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 3.0, "year": 2019}, {"source": "70", "target": "79", "source_name": "meissner effect", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2019}, {"source": "70", "target": "87", "source_name": "meissner effect", "target_name": "charge transfer", "weight": 1.0, "year": 2019}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 3.0, "year": 2019}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2019}, {"source": "71", "target": "73", "source_name": "van hove", "target_name": "room temperature", "weight": 1.0, "year": 2019}, {"source": "72", "target": "73", "source_name": "electrical resistance", "target_name": "room temperature", "weight": 4.0, "year": 2019}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 3.0, "year": 2019}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2019}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2019}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2019}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2019}, {"source": "73", "target": "79", "source_name": "room temperature", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2019}, {"source": "73", "target": "84", "source_name": "room temperature", "target_name": "ground state", "weight": 2.0, "year": 2019}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2019}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2019}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 5.0, "year": 2019}, {"source": "73", "target": "92", "source_name": "room temperature", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2019}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2019}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2019}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 6.0, "year": 2019}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2019}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2019}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2019}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "79", "target": "84", "source_name": "crystal structure", "target_name": "ground state", "weight": 2.0, "year": 2019}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 2.0, "year": 2019}, {"source": "79", "target": "90", "source_name": "crystal structure", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "79", "target": "91", "source_name": "crystal structure", "target_name": "heat capacity", "weight": 2.0, "year": 2019}, {"source": "79", "target": "92", "source_name": "crystal structure", "target_name": "ab initio", "weight": 4.0, "year": 2019}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2019}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 2.0, "year": 2019}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 2.0, "year": 2019}, {"source": "81", "target": "88", "source_name": "finite element", "target_name": "energy storage", "weight": 1.0, "year": 2019}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 4.0, "year": 2019}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "87", "target": "90", "source_name": "charge transfer", "target_name": "cooper pair", "weight": 4.0, "year": 2019}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2019}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2019}, {"source": "91", "target": "92", "source_name": "heat capacity", "target_name": "ab initio", "weight": 1.0, "year": 2019}]}, {"2020": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2020}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2020}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2020}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2020}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 4.0, "year": 2020}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2020}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2020}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 24.0, "year": 2020}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 2.0, "year": 2020}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 5.0, "year": 2020}, {"source": "1", "target": "5", "source_name": "critical temperature", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2020}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 2.0, "year": 2020}, {"source": "1", "target": "9", "source_name": "critical temperature", "target_name": "condensed matter physics", "weight": 2.0, "year": 2020}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 12.0, "year": 2020}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2020}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 2.0, "year": 2020}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2020}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 2.0, "year": 2020}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2020}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 11.0, "year": 2020}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2020}, {"source": "1", "target": "18", "source_name": "critical temperature", "target_name": "fermi arcs", "weight": 5.0, "year": 2020}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 7.0, "year": 2020}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 16.0, "year": 2020}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 4.0, "year": 2020}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 3.0, "year": 2020}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 8.0, "year": 2020}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2020}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 11.0, "year": 2020}, {"source": "1", "target": "29", "source_name": "critical temperature", "target_name": "raman scattering", "weight": 2.0, "year": 2020}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 10.0, "year": 2020}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2020}, {"source": "1", "target": "33", "source_name": "critical temperature", "target_name": "strontium titanate", "weight": 4.0, "year": 2020}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 10.0, "year": 2020}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 4.0, "year": 2020}, {"source": "1", "target": "36", "source_name": "critical temperature", "target_name": "ion beam", "weight": 1.0, "year": 2020}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 8.0, "year": 2020}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 2.0, "year": 2020}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 37.0, "year": 2020}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 4.0, "year": 2020}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 4.0, "year": 2020}, {"source": "1", "target": "43", "source_name": "critical temperature", "target_name": "transmission electron microscopy", "weight": 5.0, "year": 2020}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 16.0, "year": 2020}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 6.0, "year": 2020}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 10.0, "year": 2020}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 11.0, "year": 2020}, {"source": "1", "target": "52", "source_name": "critical temperature", "target_name": "hydrogen sulfide", "weight": 5.0, "year": 2020}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 7.0, "year": 2020}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 4.0, "year": 2020}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 7.0, "year": 2020}, {"source": "1", "target": "57", "source_name": "critical temperature", "target_name": "density functional theory", "weight": 8.0, "year": 2020}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 15.0, "year": 2020}, {"source": "1", "target": "59", "source_name": "critical temperature", "target_name": "monte carlo", "weight": 3.0, "year": 2020}, {"source": "1", "target": "60", "source_name": "critical temperature", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2020}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 25.0, "year": 2020}, {"source": "1", "target": "66", "source_name": "critical temperature", "target_name": "sulfur hydride", "weight": 8.0, "year": 2020}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2020}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 6.0, "year": 2020}, {"source": "1", "target": "69", "source_name": "critical temperature", "target_name": "selenium hydrides", "weight": 2.0, "year": 2020}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 4.0, "year": 2020}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 1.0, "year": 2020}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 7.0, "year": 2020}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 21.0, "year": 2020}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2020}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 4.0, "year": 2020}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 7.0, "year": 2020}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 9.0, "year": 2020}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2020}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2020}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 7.0, "year": 2020}, {"source": "1", "target": "85", "source_name": "critical temperature", "target_name": "perturbation theory", "weight": 1.0, "year": 2020}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 5.0, "year": 2020}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 17.0, "year": 2020}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 7.0, "year": 2020}, {"source": "2", "target": "4", "source_name": "current density", "target_name": "penetration depth", "weight": 1.0, "year": 2020}, {"source": "2", "target": "5", "source_name": "current density", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2020}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2020}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2020}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 9.0, "year": 2020}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2020}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2020}, {"source": "2", "target": "14", "source_name": "current density", "target_name": "iron selenide", "weight": 1.0, "year": 2020}, {"source": "2", "target": "15", "source_name": "current density", "target_name": "magnetic flux", "weight": 2.0, "year": 2020}, {"source": "2", "target": "17", "source_name": "current density", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2020}, {"source": "2", "target": "18", "source_name": "current density", "target_name": "fermi arcs", "weight": 5.0, "year": 2020}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2020}, {"source": "2", "target": "20", "source_name": "current density", "target_name": "specific heat", "weight": 6.0, "year": 2020}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 3.0, "year": 2020}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2020}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2020}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 3.0, "year": 2020}, {"source": "2", "target": "28", "source_name": "current density", "target_name": "bcs theory", "weight": 1.0, "year": 2020}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2020}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2020}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 2.0, "year": 2020}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 1.0, "year": 2020}, {"source": "2", "target": "39", "source_name": "current density", "target_name": "finite element method", "weight": 1.0, "year": 2020}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 43.0, "year": 2020}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 4.0, "year": 2020}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 1.0, "year": 2020}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "2", "target": "45", "source_name": "current density", "target_name": "power transmission", "weight": 1.0, "year": 2020}, {"source": "2", "target": "47", "source_name": "current density", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 6.0, "year": 2020}, {"source": "2", "target": "51", "source_name": "current density", "target_name": "wind turbine", "weight": 1.0, "year": 2020}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 2.0, "year": 2020}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 6.0, "year": 2020}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 3.0, "year": 2020}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 2.0, "year": 2020}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2020}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 3.0, "year": 2020}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 8.0, "year": 2020}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2020}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2020}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 3.0, "year": 2020}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 8.0, "year": 2020}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2020}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 6.0, "year": 2020}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2020}, {"source": "2", "target": "79", "source_name": "current density", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "2", "target": "80", "source_name": "current density", "target_name": "quench propagation", "weight": 1.0, "year": 2020}, {"source": "2", "target": "81", "source_name": "current density", "target_name": "finite element", "weight": 2.0, "year": 2020}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2020}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 5.0, "year": 2020}, {"source": "2", "target": "86", "source_name": "current density", "target_name": "induction motor", "weight": 1.0, "year": 2020}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 4.0, "year": 2020}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 2.0, "year": 2020}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 2.0, "year": 2020}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2020}, {"source": "3", "target": "23", "source_name": "charge density waves", "target_name": "order parameter", "weight": 1.0, "year": 2020}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 2.0, "year": 2020}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 1.0, "year": 2020}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 1.0, "year": 2020}, {"source": "3", "target": "44", "source_name": "charge density waves", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "3", "target": "73", "source_name": "charge density waves", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "4", "target": "14", "source_name": "penetration depth", "target_name": "iron selenide", "weight": 1.0, "year": 2020}, {"source": "4", "target": "17", "source_name": "penetration depth", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2020}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2020}, {"source": "4", "target": "20", "source_name": "penetration depth", "target_name": "specific heat", "weight": 2.0, "year": 2020}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2020}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 2.0, "year": 2020}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 4.0, "year": 2020}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "4", "target": "52", "source_name": "penetration depth", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2020}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2020}, {"source": "4", "target": "55", "source_name": "penetration depth", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "4", "target": "57", "source_name": "penetration depth", "target_name": "density functional theory", "weight": 1.0, "year": 2020}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 3.0, "year": 2020}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2020}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "5", "target": "23", "source_name": "chemical vapor deposition", "target_name": "order parameter", "weight": 1.0, "year": 2020}, {"source": "5", "target": "36", "source_name": "chemical vapor deposition", "target_name": "ion beam", "weight": 1.0, "year": 2020}, {"source": "5", "target": "40", "source_name": "chemical vapor deposition", "target_name": "magnetic field", "weight": 1.0, "year": 2020}, {"source": "5", "target": "88", "source_name": "chemical vapor deposition", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 2.0, "year": 2020}, {"source": "6", "target": "10", "source_name": "brillouin zone", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2020}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 2.0, "year": 2020}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2020}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 4.0, "year": 2020}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 2.0, "year": 2020}, {"source": "6", "target": "34", "source_name": "brillouin zone", "target_name": "exchange interaction", "weight": 1.0, "year": 2020}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 6.0, "year": 2020}, {"source": "6", "target": "44", "source_name": "brillouin zone", "target_name": "phase diagram", "weight": 4.0, "year": 2020}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2020}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 4.0, "year": 2020}, {"source": "6", "target": "57", "source_name": "brillouin zone", "target_name": "density functional theory", "weight": 1.0, "year": 2020}, {"source": "6", "target": "79", "source_name": "brillouin zone", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 3.0, "year": 2020}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 4.0, "year": 2020}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2020}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2020}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2020}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2020}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2020}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 5.0, "year": 2020}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2020}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2020}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 4.0, "year": 2020}, {"source": "7", "target": "59", "source_name": "kinetic energy", "target_name": "monte carlo", "weight": 1.0, "year": 2020}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2020}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2020}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "8", "target": "22", "source_name": "symmetry breaking", "target_name": "unit cell", "weight": 1.0, "year": 2020}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2020}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2020}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "9", "target": "10", "source_name": "condensed matter physics", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2020}, {"source": "9", "target": "17", "source_name": "condensed matter physics", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2020}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 3.0, "year": 2020}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2020}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2020}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 24.0, "year": 2020}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 2.0, "year": 2020}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2020}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2020}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2020}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2020}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2020}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "9", "target": "58", "source_name": "condensed matter physics", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2020}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 3.0, "year": 2020}, {"source": "9", "target": "73", "source_name": "condensed matter physics", "target_name": "room temperature", "weight": 3.0, "year": 2020}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2020}, {"source": "9", "target": "87", "source_name": "condensed matter physics", "target_name": "charge transfer", "weight": 4.0, "year": 2020}, {"source": "9", "target": "90", "source_name": "condensed matter physics", "target_name": "cooper pair", "weight": 4.0, "year": 2020}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2020}, {"source": "10", "target": "13", "source_name": "liquid nitrogen", "target_name": "josephson junctions", "weight": 1.0, "year": 2020}, {"source": "10", "target": "14", "source_name": "liquid nitrogen", "target_name": "iron selenide", "weight": 1.0, "year": 2020}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2020}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 2.0, "year": 2020}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2020}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2020}, {"source": "10", "target": "22", "source_name": "liquid nitrogen", "target_name": "unit cell", "weight": 2.0, "year": 2020}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2020}, {"source": "10", "target": "27", "source_name": "liquid nitrogen", "target_name": "ac losses", "weight": 1.0, "year": 2020}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2020}, {"source": "10", "target": "31", "source_name": "liquid nitrogen", "target_name": "condensed matter", "weight": 1.0, "year": 2020}, {"source": "10", "target": "33", "source_name": "liquid nitrogen", "target_name": "strontium titanate", "weight": 1.0, "year": 2020}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 2.0, "year": 2020}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 2.0, "year": 2020}, {"source": "10", "target": "39", "source_name": "liquid nitrogen", "target_name": "finite element method", "weight": 1.0, "year": 2020}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 21.0, "year": 2020}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2020}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 2.0, "year": 2020}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2020}, {"source": "10", "target": "44", "source_name": "liquid nitrogen", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 5.0, "year": 2020}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2020}, {"source": "10", "target": "51", "source_name": "liquid nitrogen", "target_name": "wind turbine", "weight": 1.0, "year": 2020}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 3.0, "year": 2020}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2020}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2020}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2020}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2020}, {"source": "10", "target": "66", "source_name": "liquid nitrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2020}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2020}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2020}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 2.0, "year": 2020}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 5.0, "year": 2020}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2020}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2020}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2020}, {"source": "10", "target": "79", "source_name": "liquid nitrogen", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "10", "target": "80", "source_name": "liquid nitrogen", "target_name": "quench propagation", "weight": 1.0, "year": 2020}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 2.0, "year": 2020}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 3.0, "year": 2020}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2020}, {"source": "10", "target": "86", "source_name": "liquid nitrogen", "target_name": "induction motor", "weight": 1.0, "year": 2020}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 5.0, "year": 2020}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 2.0, "year": 2020}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "10", "target": "92", "source_name": "liquid nitrogen", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "11", "target": "13", "source_name": "yttrium barium copper oxide", "target_name": "josephson junctions", "weight": 1.0, "year": 2020}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2020}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 3.0, "year": 2020}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2020}, {"source": "11", "target": "51", "source_name": "yttrium barium copper oxide", "target_name": "wind turbine", "weight": 1.0, "year": 2020}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 10.0, "year": 2020}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2020}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "11", "target": "79", "source_name": "yttrium barium copper oxide", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 6.0, "year": 2020}, {"source": "12", "target": "19", "source_name": "scanning tunneling microscopy", "target_name": "electric field", "weight": 2.0, "year": 2020}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2020}, {"source": "12", "target": "22", "source_name": "scanning tunneling microscopy", "target_name": "unit cell", "weight": 5.0, "year": 2020}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 6.0, "year": 2020}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2020}, {"source": "12", "target": "58", "source_name": "scanning tunneling microscopy", "target_name": "single crystal", "weight": 3.0, "year": 2020}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2020}, {"source": "12", "target": "60", "source_name": "scanning tunneling microscopy", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "12", "target": "87", "source_name": "scanning tunneling microscopy", "target_name": "charge transfer", "weight": 3.0, "year": 2020}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2020}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2020}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2020}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 4.0, "year": 2020}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2020}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2020}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 2.0, "year": 2020}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2020}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2020}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2020}, {"source": "13", "target": "65", "source_name": "josephson junctions", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2020}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "14", "target": "20", "source_name": "iron selenide", "target_name": "specific heat", "weight": 1.0, "year": 2020}, {"source": "14", "target": "22", "source_name": "iron selenide", "target_name": "unit cell", "weight": 1.0, "year": 2020}, {"source": "14", "target": "28", "source_name": "iron selenide", "target_name": "bcs theory", "weight": 1.0, "year": 2020}, {"source": "14", "target": "33", "source_name": "iron selenide", "target_name": "strontium titanate", "weight": 3.0, "year": 2020}, {"source": "14", "target": "40", "source_name": "iron selenide", "target_name": "magnetic field", "weight": 1.0, "year": 2020}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2020}, {"source": "15", "target": "20", "source_name": "magnetic flux", "target_name": "specific heat", "weight": 1.0, "year": 2020}, {"source": "15", "target": "23", "source_name": "magnetic flux", "target_name": "order parameter", "weight": 1.0, "year": 2020}, {"source": "15", "target": "32", "source_name": "magnetic flux", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2020}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2020}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 11.0, "year": 2020}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 3.0, "year": 2020}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 2.0, "year": 2020}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 3.0, "year": 2020}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2020}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "15", "target": "83", "source_name": "magnetic flux", "target_name": "permanent magnet", "weight": 1.0, "year": 2020}, {"source": "15", "target": "88", "source_name": "magnetic flux", "target_name": "energy storage", "weight": 2.0, "year": 2020}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 2.0, "year": 2020}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2020}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2020}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 3.0, "year": 2020}, {"source": "16", "target": "34", "source_name": "coulomb repulsion", "target_name": "exchange interaction", "weight": 4.0, "year": 2020}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 2.0, "year": 2020}, {"source": "16", "target": "40", "source_name": "coulomb repulsion", "target_name": "magnetic field", "weight": 1.0, "year": 2020}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 2.0, "year": 2020}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 7.0, "year": 2020}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 6.0, "year": 2020}, {"source": "16", "target": "57", "source_name": "coulomb repulsion", "target_name": "density functional theory", "weight": 1.0, "year": 2020}, {"source": "16", "target": "59", "source_name": "coulomb repulsion", "target_name": "monte carlo", "weight": 3.0, "year": 2020}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "16", "target": "72", "source_name": "coulomb repulsion", "target_name": "electrical resistance", "weight": 1.0, "year": 2020}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2020}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2020}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 3.0, "year": 2020}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "17", "target": "19", "source_name": "molecular beam epitaxy", "target_name": "electric field", "weight": 3.0, "year": 2020}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 5.0, "year": 2020}, {"source": "17", "target": "31", "source_name": "molecular beam epitaxy", "target_name": "condensed matter", "weight": 4.0, "year": 2020}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 8.0, "year": 2020}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2020}, {"source": "17", "target": "54", "source_name": "molecular beam epitaxy", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 4.0, "year": 2020}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 3.0, "year": 2020}, {"source": "17", "target": "70", "source_name": "molecular beam epitaxy", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 2.0, "year": 2020}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 6.0, "year": 2020}, {"source": "17", "target": "90", "source_name": "molecular beam epitaxy", "target_name": "cooper pair", "weight": 5.0, "year": 2020}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 7.0, "year": 2020}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2020}, {"source": "18", "target": "30", "source_name": "fermi arcs", "target_name": "fermi level", "weight": 1.0, "year": 2020}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2020}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 7.0, "year": 2020}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2020}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 7.0, "year": 2020}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2020}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2020}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 11.0, "year": 2020}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "19", "target": "50", "source_name": "electric field", "target_name": "coated conductor", "weight": 1.0, "year": 2020}, {"source": "19", "target": "58", "source_name": "electric field", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "19", "target": "65", "source_name": "electric field", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 3.0, "year": 2020}, {"source": "19", "target": "87", "source_name": "electric field", "target_name": "charge transfer", "weight": 1.0, "year": 2020}, {"source": "19", "target": "91", "source_name": "electric field", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "20", "target": "22", "source_name": "specific heat", "target_name": "unit cell", "weight": 1.0, "year": 2020}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 3.0, "year": 2020}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 4.0, "year": 2020}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 8.0, "year": 2020}, {"source": "20", "target": "35", "source_name": "specific heat", "target_name": "space group", "weight": 3.0, "year": 2020}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 3.0, "year": 2020}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 12.0, "year": 2020}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2020}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 6.0, "year": 2020}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 6.0, "year": 2020}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2020}, {"source": "20", "target": "52", "source_name": "specific heat", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2020}, {"source": "20", "target": "54", "source_name": "specific heat", "target_name": "coherence length", "weight": 2.0, "year": 2020}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2020}, {"source": "20", "target": "57", "source_name": "specific heat", "target_name": "density functional theory", "weight": 1.0, "year": 2020}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 10.0, "year": 2020}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 7.0, "year": 2020}, {"source": "20", "target": "73", "source_name": "specific heat", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2020}, {"source": "20", "target": "79", "source_name": "specific heat", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2020}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 2.0, "year": 2020}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 5.0, "year": 2020}, {"source": "20", "target": "92", "source_name": "specific heat", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 3.0, "year": 2020}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2020}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "21", "target": "46", "source_name": "grain boundary", "target_name": "iron pnictides", "weight": 1.0, "year": 2020}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "22", "target": "28", "source_name": "unit cell", "target_name": "bcs theory", "weight": 1.0, "year": 2020}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 3.0, "year": 2020}, {"source": "22", "target": "33", "source_name": "unit cell", "target_name": "strontium titanate", "weight": 1.0, "year": 2020}, {"source": "22", "target": "37", "source_name": "unit cell", "target_name": "fermi surface", "weight": 1.0, "year": 2020}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 4.0, "year": 2020}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "22", "target": "49", "source_name": "unit cell", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 2.0, "year": 2020}, {"source": "22", "target": "57", "source_name": "unit cell", "target_name": "density functional theory", "weight": 3.0, "year": 2020}, {"source": "22", "target": "58", "source_name": "unit cell", "target_name": "single crystal", "weight": 3.0, "year": 2020}, {"source": "22", "target": "65", "source_name": "unit cell", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "22", "target": "70", "source_name": "unit cell", "target_name": "meissner effect", "weight": 2.0, "year": 2020}, {"source": "22", "target": "73", "source_name": "unit cell", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "22", "target": "87", "source_name": "unit cell", "target_name": "charge transfer", "weight": 2.0, "year": 2020}, {"source": "23", "target": "26", "source_name": "order parameter", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2020}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2020}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2020}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2020}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 9.0, "year": 2020}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 2.0, "year": 2020}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 6.0, "year": 2020}, {"source": "23", "target": "41", "source_name": "order parameter", "target_name": "grain boundaries", "weight": 1.0, "year": 2020}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 5.0, "year": 2020}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2020}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2020}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2020}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 3.0, "year": 2020}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2020}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 3.0, "year": 2020}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2020}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2020}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2020}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2020}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2020}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2020}, {"source": "23", "target": "73", "source_name": "order parameter", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2020}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2020}, {"source": "23", "target": "88", "source_name": "order parameter", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 6.0, "year": 2020}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 4.0, "year": 2020}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2020}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 2.0, "year": 2020}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "24", "target": "64", "source_name": "magnetic resonance imaging", "target_name": "liquid helium", "weight": 1.0, "year": 2020}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2020}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2020}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 3.0, "year": 2020}, {"source": "24", "target": "88", "source_name": "magnetic resonance imaging", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "26", "target": "30", "source_name": "carbon nanotubes", "target_name": "fermi level", "weight": 1.0, "year": 2020}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2020}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "26", "target": "71", "source_name": "carbon nanotubes", "target_name": "van hove", "weight": 1.0, "year": 2020}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "26", "target": "90", "source_name": "carbon nanotubes", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "27", "target": "39", "source_name": "ac losses", "target_name": "finite element method", "weight": 1.0, "year": 2020}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 6.0, "year": 2020}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2020}, {"source": "27", "target": "45", "source_name": "ac losses", "target_name": "power transmission", "weight": 1.0, "year": 2020}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2020}, {"source": "27", "target": "51", "source_name": "ac losses", "target_name": "wind turbine", "weight": 1.0, "year": 2020}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2020}, {"source": "27", "target": "62", "source_name": "ac losses", "target_name": "alternating current", "weight": 1.0, "year": 2020}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2020}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2020}, {"source": "27", "target": "81", "source_name": "ac losses", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "27", "target": "86", "source_name": "ac losses", "target_name": "induction motor", "weight": 1.0, "year": 2020}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 2.0, "year": 2020}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2020}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 3.0, "year": 2020}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2020}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 5.0, "year": 2020}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2020}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2020}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2020}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2020}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2020}, {"source": "28", "target": "58", "source_name": "bcs theory", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 3.0, "year": 2020}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2020}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2020}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2020}, {"source": "28", "target": "79", "source_name": "bcs theory", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2020}, {"source": "28", "target": "92", "source_name": "bcs theory", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2020}, {"source": "29", "target": "40", "source_name": "raman scattering", "target_name": "magnetic field", "weight": 1.0, "year": 2020}, {"source": "29", "target": "44", "source_name": "raman scattering", "target_name": "phase diagram", "weight": 2.0, "year": 2020}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2020}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2020}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 4.0, "year": 2020}, {"source": "29", "target": "70", "source_name": "raman scattering", "target_name": "meissner effect", "weight": 2.0, "year": 2020}, {"source": "29", "target": "87", "source_name": "raman scattering", "target_name": "charge transfer", "weight": 1.0, "year": 2020}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2020}, {"source": "30", "target": "35", "source_name": "fermi level", "target_name": "space group", "weight": 1.0, "year": 2020}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 3.0, "year": 2020}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2020}, {"source": "30", "target": "47", "source_name": "fermi level", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "30", "target": "54", "source_name": "fermi level", "target_name": "coherence length", "weight": 2.0, "year": 2020}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 2.0, "year": 2020}, {"source": "30", "target": "58", "source_name": "fermi level", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "30", "target": "60", "source_name": "fermi level", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "30", "target": "65", "source_name": "fermi level", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 3.0, "year": 2020}, {"source": "30", "target": "72", "source_name": "fermi level", "target_name": "electrical resistance", "weight": 1.0, "year": 2020}, {"source": "30", "target": "73", "source_name": "fermi level", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "30", "target": "79", "source_name": "fermi level", "target_name": "crystal structure", "weight": 3.0, "year": 2020}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "30", "target": "91", "source_name": "fermi level", "target_name": "heat capacity", "weight": 3.0, "year": 2020}, {"source": "30", "target": "92", "source_name": "fermi level", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "31", "target": "37", "source_name": "condensed matter", "target_name": "fermi surface", "weight": 1.0, "year": 2020}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2020}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2020}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2020}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 2.0, "year": 2020}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2020}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "31", "target": "58", "source_name": "condensed matter", "target_name": "single crystal", "weight": 5.0, "year": 2020}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2020}, {"source": "31", "target": "62", "source_name": "condensed matter", "target_name": "alternating current", "weight": 1.0, "year": 2020}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2020}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 3.0, "year": 2020}, {"source": "31", "target": "68", "source_name": "condensed matter", "target_name": "nuclear magnetic resonance", "weight": 3.0, "year": 2020}, {"source": "31", "target": "73", "source_name": "condensed matter", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2020}, {"source": "31", "target": "87", "source_name": "condensed matter", "target_name": "charge transfer", "weight": 4.0, "year": 2020}, {"source": "31", "target": "90", "source_name": "condensed matter", "target_name": "cooper pair", "weight": 4.0, "year": 2020}, {"source": "31", "target": "91", "source_name": "condensed matter", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2020}, {"source": "32", "target": "61", "source_name": "flywheel energy storage", "target_name": "synchronous motor", "weight": 1.0, "year": 2020}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2020}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 4.0, "year": 2020}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 10.0, "year": 2020}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 2.0, "year": 2020}, {"source": "33", "target": "58", "source_name": "strontium titanate", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 4.0, "year": 2020}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2020}, {"source": "34", "target": "49", "source_name": "exchange interaction", "target_name": "strongly correlated", "weight": 4.0, "year": 2020}, {"source": "34", "target": "56", "source_name": "exchange interaction", "target_name": "hubbard model", "weight": 3.0, "year": 2020}, {"source": "34", "target": "57", "source_name": "exchange interaction", "target_name": "density functional theory", "weight": 1.0, "year": 2020}, {"source": "34", "target": "59", "source_name": "exchange interaction", "target_name": "monte carlo", "weight": 3.0, "year": 2020}, {"source": "34", "target": "66", "source_name": "exchange interaction", "target_name": "sulfur hydride", "weight": 2.0, "year": 2020}, {"source": "34", "target": "72", "source_name": "exchange interaction", "target_name": "electrical resistance", "weight": 1.0, "year": 2020}, {"source": "34", "target": "79", "source_name": "exchange interaction", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 2.0, "year": 2020}, {"source": "35", "target": "40", "source_name": "space group", "target_name": "magnetic field", "weight": 2.0, "year": 2020}, {"source": "35", "target": "47", "source_name": "space group", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2020}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 3.0, "year": 2020}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2020}, {"source": "35", "target": "79", "source_name": "space group", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "35", "target": "90", "source_name": "space group", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "35", "target": "91", "source_name": "space group", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "35", "target": "92", "source_name": "space group", "target_name": "ab initio", "weight": 2.0, "year": 2020}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 1.0, "year": 2020}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2020}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2020}, {"source": "36", "target": "54", "source_name": "ion beam", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2020}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2020}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 3.0, "year": 2020}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 4.0, "year": 2020}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2020}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2020}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2020}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 4.0, "year": 2020}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2020}, {"source": "37", "target": "57", "source_name": "fermi surface", "target_name": "density functional theory", "weight": 2.0, "year": 2020}, {"source": "37", "target": "58", "source_name": "fermi surface", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2020}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2020}, {"source": "37", "target": "68", "source_name": "fermi surface", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2020}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 5.0, "year": 2020}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 8.0, "year": 2020}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2020}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2020}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 11.0, "year": 2020}, {"source": "37", "target": "91", "source_name": "fermi surface", "target_name": "heat capacity", "weight": 2.0, "year": 2020}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "38", "target": "40", "source_name": "metallic hydrogen", "target_name": "magnetic field", "weight": 1.0, "year": 2020}, {"source": "38", "target": "42", "source_name": "metallic hydrogen", "target_name": "rare earth", "weight": 1.0, "year": 2020}, {"source": "38", "target": "66", "source_name": "metallic hydrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2020}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "38", "target": "79", "source_name": "metallic hydrogen", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2020}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 3.0, "year": 2020}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 11.0, "year": 2020}, {"source": "39", "target": "42", "source_name": "finite element method", "target_name": "rare earth", "weight": 1.0, "year": 2020}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2020}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 2.0, "year": 2020}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 2.0, "year": 2020}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "39", "target": "68", "source_name": "finite element method", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2020}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2020}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 15.0, "year": 2020}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 2.0, "year": 2020}, {"source": "39", "target": "86", "source_name": "finite element method", "target_name": "induction motor", "weight": 1.0, "year": 2020}, {"source": "39", "target": "88", "source_name": "finite element method", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 5.0, "year": 2020}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 6.0, "year": 2020}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 14.0, "year": 2020}, {"source": "40", "target": "46", "source_name": "magnetic field", "target_name": "iron pnictides", "weight": 1.0, "year": 2020}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 12.0, "year": 2020}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2020}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 14.0, "year": 2020}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 4.0, "year": 2020}, {"source": "40", "target": "52", "source_name": "magnetic field", "target_name": "hydrogen sulfide", "weight": 2.0, "year": 2020}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 10.0, "year": 2020}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2020}, {"source": "40", "target": "57", "source_name": "magnetic field", "target_name": "density functional theory", "weight": 4.0, "year": 2020}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 25.0, "year": 2020}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 10.0, "year": 2020}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 3.0, "year": 2020}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2020}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 17.0, "year": 2020}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 13.0, "year": 2020}, {"source": "40", "target": "66", "source_name": "magnetic field", "target_name": "sulfur hydride", "weight": 2.0, "year": 2020}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2020}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 3.0, "year": 2020}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 4.0, "year": 2020}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 21.0, "year": 2020}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2020}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2020}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 10.0, "year": 2020}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 4.0, "year": 2020}, {"source": "40", "target": "79", "source_name": "magnetic field", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 4.0, "year": 2020}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 12.0, "year": 2020}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 12.0, "year": 2020}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 9.0, "year": 2020}, {"source": "40", "target": "86", "source_name": "magnetic field", "target_name": "induction motor", "weight": 1.0, "year": 2020}, {"source": "40", "target": "87", "source_name": "magnetic field", "target_name": "charge transfer", "weight": 1.0, "year": 2020}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 13.0, "year": 2020}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 5.0, "year": 2020}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2020}, {"source": "41", "target": "46", "source_name": "grain boundaries", "target_name": "iron pnictides", "weight": 1.0, "year": 2020}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2020}, {"source": "41", "target": "54", "source_name": "grain boundaries", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2020}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 2.0, "year": 2020}, {"source": "41", "target": "79", "source_name": "grain boundaries", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 3.0, "year": 2020}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2020}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "42", "target": "66", "source_name": "rare earth", "target_name": "sulfur hydride", "weight": 1.0, "year": 2020}, {"source": "42", "target": "68", "source_name": "rare earth", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2020}, {"source": "42", "target": "73", "source_name": "rare earth", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2020}, {"source": "42", "target": "79", "source_name": "rare earth", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "42", "target": "81", "source_name": "rare earth", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2020}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "42", "target": "92", "source_name": "rare earth", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "43", "target": "68", "source_name": "transmission electron microscopy", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2020}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2020}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 6.0, "year": 2020}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 5.0, "year": 2020}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 6.0, "year": 2020}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 5.0, "year": 2020}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2020}, {"source": "44", "target": "53", "source_name": "phase diagram", "target_name": "spectral weight", "weight": 1.0, "year": 2020}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2020}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 3.0, "year": 2020}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 6.0, "year": 2020}, {"source": "44", "target": "57", "source_name": "phase diagram", "target_name": "density functional theory", "weight": 2.0, "year": 2020}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 12.0, "year": 2020}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 3.0, "year": 2020}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 3.0, "year": 2020}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2020}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 10.0, "year": 2020}, {"source": "44", "target": "66", "source_name": "phase diagram", "target_name": "sulfur hydride", "weight": 4.0, "year": 2020}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2020}, {"source": "44", "target": "69", "source_name": "phase diagram", "target_name": "selenium hydrides", "weight": 5.0, "year": 2020}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2020}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 7.0, "year": 2020}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2020}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2020}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 4.0, "year": 2020}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2020}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 8.0, "year": 2020}, {"source": "44", "target": "85", "source_name": "phase diagram", "target_name": "perturbation theory", "weight": 1.0, "year": 2020}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 2.0, "year": 2020}, {"source": "44", "target": "92", "source_name": "phase diagram", "target_name": "ab initio", "weight": 2.0, "year": 2020}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2020}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2020}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "46", "target": "47", "source_name": "iron pnictides", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2020}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2020}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 2.0, "year": 2020}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2020}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "46", "target": "55", "source_name": "iron pnictides", "target_name": "optimally doped", "weight": 2.0, "year": 2020}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2020}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2020}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2020}, {"source": "46", "target": "73", "source_name": "iron pnictides", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "46", "target": "84", "source_name": "iron pnictides", "target_name": "ground state", "weight": 2.0, "year": 2020}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2020}, {"source": "46", "target": "90", "source_name": "iron pnictides", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "47", "target": "49", "source_name": "magnetic susceptibility", "target_name": "strongly correlated", "weight": 1.0, "year": 2020}, {"source": "47", "target": "52", "source_name": "magnetic susceptibility", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2020}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 2.0, "year": 2020}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 6.0, "year": 2020}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2020}, {"source": "47", "target": "66", "source_name": "magnetic susceptibility", "target_name": "sulfur hydride", "weight": 4.0, "year": 2020}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 5.0, "year": 2020}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 4.0, "year": 2020}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 5.0, "year": 2020}, {"source": "47", "target": "84", "source_name": "magnetic susceptibility", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "47", "target": "87", "source_name": "magnetic susceptibility", "target_name": "charge transfer", "weight": 1.0, "year": 2020}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 2.0, "year": 2020}, {"source": "47", "target": "91", "source_name": "magnetic susceptibility", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 6.0, "year": 2020}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2020}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2020}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2020}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 6.0, "year": 2020}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2020}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 4.0, "year": 2020}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 10.0, "year": 2020}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 11.0, "year": 2020}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2020}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 3.0, "year": 2020}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2020}, {"source": "49", "target": "73", "source_name": "strongly correlated", "target_name": "room temperature", "weight": 3.0, "year": 2020}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2020}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 7.0, "year": 2020}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2020}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2020}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2020}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2020}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2020}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2020}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2020}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 2.0, "year": 2020}, {"source": "50", "target": "88", "source_name": "coated conductor", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2020}, {"source": "50", "target": "91", "source_name": "coated conductor", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 4.0, "year": 2020}, {"source": "51", "target": "86", "source_name": "wind turbine", "target_name": "induction motor", "weight": 1.0, "year": 2020}, {"source": "52", "target": "57", "source_name": "hydrogen sulfide", "target_name": "density functional theory", "weight": 1.0, "year": 2020}, {"source": "52", "target": "66", "source_name": "hydrogen sulfide", "target_name": "sulfur hydride", "weight": 2.0, "year": 2020}, {"source": "52", "target": "73", "source_name": "hydrogen sulfide", "target_name": "room temperature", "weight": 3.0, "year": 2020}, {"source": "52", "target": "79", "source_name": "hydrogen sulfide", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "52", "target": "92", "source_name": "hydrogen sulfide", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2020}, {"source": "53", "target": "55", "source_name": "spectral weight", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 3.0, "year": 2020}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 4.0, "year": 2020}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2020}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 7.0, "year": 2020}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 3.0, "year": 2020}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2020}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 2.0, "year": 2020}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2020}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2020}, {"source": "54", "target": "79", "source_name": "coherence length", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 5.0, "year": 2020}, {"source": "54", "target": "91", "source_name": "coherence length", "target_name": "heat capacity", "weight": 2.0, "year": 2020}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 2.0, "year": 2020}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 3.0, "year": 2020}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 3.0, "year": 2020}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2020}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2020}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 10.0, "year": 2020}, {"source": "56", "target": "60", "source_name": "hubbard model", "target_name": "mott insulator", "weight": 1.0, "year": 2020}, {"source": "56", "target": "65", "source_name": "hubbard model", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 4.0, "year": 2020}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2020}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 3.0, "year": 2020}, {"source": "57", "target": "69", "source_name": "density functional theory", "target_name": "selenium hydrides", "weight": 2.0, "year": 2020}, {"source": "57", "target": "73", "source_name": "density functional theory", "target_name": "room temperature", "weight": 4.0, "year": 2020}, {"source": "57", "target": "79", "source_name": "density functional theory", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "57", "target": "90", "source_name": "density functional theory", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "57", "target": "92", "source_name": "density functional theory", "target_name": "ab initio", "weight": 2.0, "year": 2020}, {"source": "58", "target": "62", "source_name": "single crystal", "target_name": "alternating current", "weight": 1.0, "year": 2020}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 4.0, "year": 2020}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2020}, {"source": "58", "target": "68", "source_name": "single crystal", "target_name": "nuclear magnetic resonance", "weight": 3.0, "year": 2020}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2020}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 3.0, "year": 2020}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 4.0, "year": 2020}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2020}, {"source": "58", "target": "84", "source_name": "single crystal", "target_name": "ground state", "weight": 2.0, "year": 2020}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 5.0, "year": 2020}, {"source": "58", "target": "91", "source_name": "single crystal", "target_name": "heat capacity", "weight": 3.0, "year": 2020}, {"source": "59", "target": "73", "source_name": "monte carlo", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 8.0, "year": 2020}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 2.0, "year": 2020}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2020}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2020}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "61", "target": "64", "source_name": "synchronous motor", "target_name": "liquid helium", "weight": 1.0, "year": 2020}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 2.0, "year": 2020}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 3.0, "year": 2020}, {"source": "61", "target": "88", "source_name": "synchronous motor", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "62", "target": "65", "source_name": "alternating current", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "62", "target": "77", "source_name": "alternating current", "target_name": "magnetic levitation", "weight": 1.0, "year": 2020}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "62", "target": "83", "source_name": "alternating current", "target_name": "permanent magnet", "weight": 1.0, "year": 2020}, {"source": "62", "target": "91", "source_name": "alternating current", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2020}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2020}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2020}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2020}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2020}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2020}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2020}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2020}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2020}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 2.0, "year": 2020}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2020}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2020}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2020}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2020}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 4.0, "year": 2020}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 4.0, "year": 2020}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2020}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2020}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 5.0, "year": 2020}, {"source": "65", "target": "91", "source_name": "copper oxide", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "66", "target": "69", "source_name": "sulfur hydride", "target_name": "selenium hydrides", "weight": 4.0, "year": 2020}, {"source": "66", "target": "70", "source_name": "sulfur hydride", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "66", "target": "73", "source_name": "sulfur hydride", "target_name": "room temperature", "weight": 2.0, "year": 2020}, {"source": "66", "target": "79", "source_name": "sulfur hydride", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2020}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2020}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2020}, {"source": "67", "target": "88", "source_name": "magnesium diboride", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2020}, {"source": "68", "target": "77", "source_name": "nuclear magnetic resonance", "target_name": "magnetic levitation", "weight": 1.0, "year": 2020}, {"source": "68", "target": "79", "source_name": "nuclear magnetic resonance", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "68", "target": "81", "source_name": "nuclear magnetic resonance", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 3.0, "year": 2020}, {"source": "70", "target": "79", "source_name": "meissner effect", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2020}, {"source": "70", "target": "87", "source_name": "meissner effect", "target_name": "charge transfer", "weight": 1.0, "year": 2020}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 3.0, "year": 2020}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2020}, {"source": "71", "target": "73", "source_name": "van hove", "target_name": "room temperature", "weight": 1.0, "year": 2020}, {"source": "72", "target": "73", "source_name": "electrical resistance", "target_name": "room temperature", "weight": 5.0, "year": 2020}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 3.0, "year": 2020}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2020}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2020}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2020}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2020}, {"source": "73", "target": "79", "source_name": "room temperature", "target_name": "crystal structure", "weight": 3.0, "year": 2020}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2020}, {"source": "73", "target": "84", "source_name": "room temperature", "target_name": "ground state", "weight": 3.0, "year": 2020}, {"source": "73", "target": "85", "source_name": "room temperature", "target_name": "perturbation theory", "weight": 1.0, "year": 2020}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2020}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2020}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 5.0, "year": 2020}, {"source": "73", "target": "92", "source_name": "room temperature", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2020}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2020}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2020}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 6.0, "year": 2020}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2020}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2020}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2020}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "79", "target": "84", "source_name": "crystal structure", "target_name": "ground state", "weight": 2.0, "year": 2020}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 3.0, "year": 2020}, {"source": "79", "target": "90", "source_name": "crystal structure", "target_name": "cooper pair", "weight": 2.0, "year": 2020}, {"source": "79", "target": "91", "source_name": "crystal structure", "target_name": "heat capacity", "weight": 2.0, "year": 2020}, {"source": "79", "target": "92", "source_name": "crystal structure", "target_name": "ab initio", "weight": 5.0, "year": 2020}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2020}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 2.0, "year": 2020}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 2.0, "year": 2020}, {"source": "81", "target": "88", "source_name": "finite element", "target_name": "energy storage", "weight": 1.0, "year": 2020}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 4.0, "year": 2020}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "87", "target": "90", "source_name": "charge transfer", "target_name": "cooper pair", "weight": 4.0, "year": 2020}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2020}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2020}, {"source": "91", "target": "92", "source_name": "heat capacity", "target_name": "ab initio", "weight": 1.0, "year": 2020}]}, {"2021": [{"source": "0", "target": "1", "source_name": "ship propulsion", "target_name": "critical temperature", "weight": 1.0, "year": 2021}, {"source": "0", "target": "2", "source_name": "ship propulsion", "target_name": "current density", "weight": 2.0, "year": 2021}, {"source": "0", "target": "10", "source_name": "ship propulsion", "target_name": "liquid nitrogen", "weight": 2.0, "year": 2021}, {"source": "0", "target": "37", "source_name": "ship propulsion", "target_name": "fermi surface", "weight": 1.0, "year": 2021}, {"source": "0", "target": "40", "source_name": "ship propulsion", "target_name": "magnetic field", "weight": 4.0, "year": 2021}, {"source": "0", "target": "51", "source_name": "ship propulsion", "target_name": "wind turbine", "weight": 1.0, "year": 2021}, {"source": "0", "target": "61", "source_name": "ship propulsion", "target_name": "synchronous motor", "weight": 3.0, "year": 2021}, {"source": "1", "target": "2", "source_name": "critical temperature", "target_name": "current density", "weight": 28.0, "year": 2021}, {"source": "1", "target": "3", "source_name": "critical temperature", "target_name": "charge density waves", "weight": 3.0, "year": 2021}, {"source": "1", "target": "4", "source_name": "critical temperature", "target_name": "penetration depth", "weight": 5.0, "year": 2021}, {"source": "1", "target": "5", "source_name": "critical temperature", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2021}, {"source": "1", "target": "7", "source_name": "critical temperature", "target_name": "kinetic energy", "weight": 2.0, "year": 2021}, {"source": "1", "target": "9", "source_name": "critical temperature", "target_name": "condensed matter physics", "weight": 2.0, "year": 2021}, {"source": "1", "target": "10", "source_name": "critical temperature", "target_name": "liquid nitrogen", "weight": 13.0, "year": 2021}, {"source": "1", "target": "11", "source_name": "critical temperature", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2021}, {"source": "1", "target": "12", "source_name": "critical temperature", "target_name": "scanning tunneling microscopy", "weight": 2.0, "year": 2021}, {"source": "1", "target": "13", "source_name": "critical temperature", "target_name": "josephson junctions", "weight": 1.0, "year": 2021}, {"source": "1", "target": "14", "source_name": "critical temperature", "target_name": "iron selenide", "weight": 2.0, "year": 2021}, {"source": "1", "target": "15", "source_name": "critical temperature", "target_name": "magnetic flux", "weight": 1.0, "year": 2021}, {"source": "1", "target": "16", "source_name": "critical temperature", "target_name": "coulomb repulsion", "weight": 11.0, "year": 2021}, {"source": "1", "target": "17", "source_name": "critical temperature", "target_name": "molecular beam epitaxy", "weight": 5.0, "year": 2021}, {"source": "1", "target": "18", "source_name": "critical temperature", "target_name": "fermi arcs", "weight": 5.0, "year": 2021}, {"source": "1", "target": "19", "source_name": "critical temperature", "target_name": "electric field", "weight": 8.0, "year": 2021}, {"source": "1", "target": "20", "source_name": "critical temperature", "target_name": "specific heat", "weight": 16.0, "year": 2021}, {"source": "1", "target": "21", "source_name": "critical temperature", "target_name": "grain boundary", "weight": 4.0, "year": 2021}, {"source": "1", "target": "22", "source_name": "critical temperature", "target_name": "unit cell", "weight": 3.0, "year": 2021}, {"source": "1", "target": "23", "source_name": "critical temperature", "target_name": "order parameter", "weight": 8.0, "year": 2021}, {"source": "1", "target": "24", "source_name": "critical temperature", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2021}, {"source": "1", "target": "28", "source_name": "critical temperature", "target_name": "bcs theory", "weight": 11.0, "year": 2021}, {"source": "1", "target": "29", "source_name": "critical temperature", "target_name": "raman scattering", "weight": 2.0, "year": 2021}, {"source": "1", "target": "30", "source_name": "critical temperature", "target_name": "fermi level", "weight": 10.0, "year": 2021}, {"source": "1", "target": "31", "source_name": "critical temperature", "target_name": "condensed matter", "weight": 1.0, "year": 2021}, {"source": "1", "target": "33", "source_name": "critical temperature", "target_name": "strontium titanate", "weight": 4.0, "year": 2021}, {"source": "1", "target": "34", "source_name": "critical temperature", "target_name": "exchange interaction", "weight": 10.0, "year": 2021}, {"source": "1", "target": "35", "source_name": "critical temperature", "target_name": "space group", "weight": 4.0, "year": 2021}, {"source": "1", "target": "36", "source_name": "critical temperature", "target_name": "ion beam", "weight": 2.0, "year": 2021}, {"source": "1", "target": "37", "source_name": "critical temperature", "target_name": "fermi surface", "weight": 10.0, "year": 2021}, {"source": "1", "target": "38", "source_name": "critical temperature", "target_name": "metallic hydrogen", "weight": 2.0, "year": 2021}, {"source": "1", "target": "40", "source_name": "critical temperature", "target_name": "magnetic field", "weight": 46.0, "year": 2021}, {"source": "1", "target": "41", "source_name": "critical temperature", "target_name": "grain boundaries", "weight": 4.0, "year": 2021}, {"source": "1", "target": "42", "source_name": "critical temperature", "target_name": "rare earth", "weight": 4.0, "year": 2021}, {"source": "1", "target": "43", "source_name": "critical temperature", "target_name": "transmission electron microscopy", "weight": 5.0, "year": 2021}, {"source": "1", "target": "44", "source_name": "critical temperature", "target_name": "phase diagram", "weight": 18.0, "year": 2021}, {"source": "1", "target": "46", "source_name": "critical temperature", "target_name": "iron pnictides", "weight": 6.0, "year": 2021}, {"source": "1", "target": "47", "source_name": "critical temperature", "target_name": "magnetic susceptibility", "weight": 10.0, "year": 2021}, {"source": "1", "target": "49", "source_name": "critical temperature", "target_name": "strongly correlated", "weight": 11.0, "year": 2021}, {"source": "1", "target": "52", "source_name": "critical temperature", "target_name": "hydrogen sulfide", "weight": 5.0, "year": 2021}, {"source": "1", "target": "54", "source_name": "critical temperature", "target_name": "coherence length", "weight": 7.0, "year": 2021}, {"source": "1", "target": "55", "source_name": "critical temperature", "target_name": "optimally doped", "weight": 4.0, "year": 2021}, {"source": "1", "target": "56", "source_name": "critical temperature", "target_name": "hubbard model", "weight": 7.0, "year": 2021}, {"source": "1", "target": "57", "source_name": "critical temperature", "target_name": "density functional theory", "weight": 8.0, "year": 2021}, {"source": "1", "target": "58", "source_name": "critical temperature", "target_name": "single crystal", "weight": 16.0, "year": 2021}, {"source": "1", "target": "59", "source_name": "critical temperature", "target_name": "monte carlo", "weight": 3.0, "year": 2021}, {"source": "1", "target": "60", "source_name": "critical temperature", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "1", "target": "64", "source_name": "critical temperature", "target_name": "liquid helium", "weight": 3.0, "year": 2021}, {"source": "1", "target": "65", "source_name": "critical temperature", "target_name": "copper oxide", "weight": 26.0, "year": 2021}, {"source": "1", "target": "66", "source_name": "critical temperature", "target_name": "sulfur hydride", "weight": 9.0, "year": 2021}, {"source": "1", "target": "67", "source_name": "critical temperature", "target_name": "magnesium diboride", "weight": 2.0, "year": 2021}, {"source": "1", "target": "68", "source_name": "critical temperature", "target_name": "nuclear magnetic resonance", "weight": 6.0, "year": 2021}, {"source": "1", "target": "69", "source_name": "critical temperature", "target_name": "selenium hydrides", "weight": 2.0, "year": 2021}, {"source": "1", "target": "70", "source_name": "critical temperature", "target_name": "meissner effect", "weight": 4.0, "year": 2021}, {"source": "1", "target": "71", "source_name": "critical temperature", "target_name": "van hove", "weight": 2.0, "year": 2021}, {"source": "1", "target": "72", "source_name": "critical temperature", "target_name": "electrical resistance", "weight": 9.0, "year": 2021}, {"source": "1", "target": "73", "source_name": "critical temperature", "target_name": "room temperature", "weight": 22.0, "year": 2021}, {"source": "1", "target": "74", "source_name": "critical temperature", "target_name": "transmission line", "weight": 2.0, "year": 2021}, {"source": "1", "target": "77", "source_name": "critical temperature", "target_name": "magnetic levitation", "weight": 4.0, "year": 2021}, {"source": "1", "target": "78", "source_name": "critical temperature", "target_name": "charge carrier", "weight": 7.0, "year": 2021}, {"source": "1", "target": "79", "source_name": "critical temperature", "target_name": "crystal structure", "weight": 10.0, "year": 2021}, {"source": "1", "target": "80", "source_name": "critical temperature", "target_name": "quench propagation", "weight": 1.0, "year": 2021}, {"source": "1", "target": "81", "source_name": "critical temperature", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "1", "target": "82", "source_name": "critical temperature", "target_name": "insertion loss", "weight": 2.0, "year": 2021}, {"source": "1", "target": "84", "source_name": "critical temperature", "target_name": "ground state", "weight": 7.0, "year": 2021}, {"source": "1", "target": "85", "source_name": "critical temperature", "target_name": "perturbation theory", "weight": 1.0, "year": 2021}, {"source": "1", "target": "87", "source_name": "critical temperature", "target_name": "charge transfer", "weight": 5.0, "year": 2021}, {"source": "1", "target": "90", "source_name": "critical temperature", "target_name": "cooper pair", "weight": 17.0, "year": 2021}, {"source": "1", "target": "91", "source_name": "critical temperature", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "1", "target": "92", "source_name": "critical temperature", "target_name": "ab initio", "weight": 8.0, "year": 2021}, {"source": "2", "target": "4", "source_name": "current density", "target_name": "penetration depth", "weight": 3.0, "year": 2021}, {"source": "2", "target": "5", "source_name": "current density", "target_name": "chemical vapor deposition", "weight": 1.0, "year": 2021}, {"source": "2", "target": "7", "source_name": "current density", "target_name": "kinetic energy", "weight": 1.0, "year": 2021}, {"source": "2", "target": "8", "source_name": "current density", "target_name": "symmetry breaking", "weight": 1.0, "year": 2021}, {"source": "2", "target": "10", "source_name": "current density", "target_name": "liquid nitrogen", "weight": 9.0, "year": 2021}, {"source": "2", "target": "12", "source_name": "current density", "target_name": "scanning tunneling microscopy", "weight": 1.0, "year": 2021}, {"source": "2", "target": "13", "source_name": "current density", "target_name": "josephson junctions", "weight": 1.0, "year": 2021}, {"source": "2", "target": "14", "source_name": "current density", "target_name": "iron selenide", "weight": 1.0, "year": 2021}, {"source": "2", "target": "15", "source_name": "current density", "target_name": "magnetic flux", "weight": 2.0, "year": 2021}, {"source": "2", "target": "17", "source_name": "current density", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2021}, {"source": "2", "target": "18", "source_name": "current density", "target_name": "fermi arcs", "weight": 5.0, "year": 2021}, {"source": "2", "target": "19", "source_name": "current density", "target_name": "electric field", "weight": 1.0, "year": 2021}, {"source": "2", "target": "20", "source_name": "current density", "target_name": "specific heat", "weight": 6.0, "year": 2021}, {"source": "2", "target": "21", "source_name": "current density", "target_name": "grain boundary", "weight": 3.0, "year": 2021}, {"source": "2", "target": "23", "source_name": "current density", "target_name": "order parameter", "weight": 1.0, "year": 2021}, {"source": "2", "target": "24", "source_name": "current density", "target_name": "magnetic resonance imaging", "weight": 1.0, "year": 2021}, {"source": "2", "target": "27", "source_name": "current density", "target_name": "ac losses", "weight": 3.0, "year": 2021}, {"source": "2", "target": "28", "source_name": "current density", "target_name": "bcs theory", "weight": 1.0, "year": 2021}, {"source": "2", "target": "32", "source_name": "current density", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2021}, {"source": "2", "target": "35", "source_name": "current density", "target_name": "space group", "weight": 2.0, "year": 2021}, {"source": "2", "target": "36", "source_name": "current density", "target_name": "ion beam", "weight": 3.0, "year": 2021}, {"source": "2", "target": "37", "source_name": "current density", "target_name": "fermi surface", "weight": 2.0, "year": 2021}, {"source": "2", "target": "39", "source_name": "current density", "target_name": "finite element method", "weight": 1.0, "year": 2021}, {"source": "2", "target": "40", "source_name": "current density", "target_name": "magnetic field", "weight": 51.0, "year": 2021}, {"source": "2", "target": "41", "source_name": "current density", "target_name": "grain boundaries", "weight": 4.0, "year": 2021}, {"source": "2", "target": "42", "source_name": "current density", "target_name": "rare earth", "weight": 2.0, "year": 2021}, {"source": "2", "target": "43", "source_name": "current density", "target_name": "transmission electron microscopy", "weight": 3.0, "year": 2021}, {"source": "2", "target": "44", "source_name": "current density", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "2", "target": "45", "source_name": "current density", "target_name": "power transmission", "weight": 1.0, "year": 2021}, {"source": "2", "target": "47", "source_name": "current density", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "2", "target": "50", "source_name": "current density", "target_name": "coated conductor", "weight": 7.0, "year": 2021}, {"source": "2", "target": "51", "source_name": "current density", "target_name": "wind turbine", "weight": 1.0, "year": 2021}, {"source": "2", "target": "54", "source_name": "current density", "target_name": "coherence length", "weight": 2.0, "year": 2021}, {"source": "2", "target": "55", "source_name": "current density", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "2", "target": "58", "source_name": "current density", "target_name": "single crystal", "weight": 7.0, "year": 2021}, {"source": "2", "target": "61", "source_name": "current density", "target_name": "synchronous motor", "weight": 3.0, "year": 2021}, {"source": "2", "target": "62", "source_name": "current density", "target_name": "alternating current", "weight": 2.0, "year": 2021}, {"source": "2", "target": "63", "source_name": "current density", "target_name": "weak links", "weight": 2.0, "year": 2021}, {"source": "2", "target": "64", "source_name": "current density", "target_name": "liquid helium", "weight": 3.0, "year": 2021}, {"source": "2", "target": "65", "source_name": "current density", "target_name": "copper oxide", "weight": 8.0, "year": 2021}, {"source": "2", "target": "67", "source_name": "current density", "target_name": "magnesium diboride", "weight": 3.0, "year": 2021}, {"source": "2", "target": "68", "source_name": "current density", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2021}, {"source": "2", "target": "72", "source_name": "current density", "target_name": "electrical resistance", "weight": 3.0, "year": 2021}, {"source": "2", "target": "73", "source_name": "current density", "target_name": "room temperature", "weight": 8.0, "year": 2021}, {"source": "2", "target": "75", "source_name": "current density", "target_name": "stainless steel", "weight": 1.0, "year": 2021}, {"source": "2", "target": "77", "source_name": "current density", "target_name": "magnetic levitation", "weight": 6.0, "year": 2021}, {"source": "2", "target": "78", "source_name": "current density", "target_name": "charge carrier", "weight": 2.0, "year": 2021}, {"source": "2", "target": "79", "source_name": "current density", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "2", "target": "80", "source_name": "current density", "target_name": "quench propagation", "weight": 1.0, "year": 2021}, {"source": "2", "target": "81", "source_name": "current density", "target_name": "finite element", "weight": 2.0, "year": 2021}, {"source": "2", "target": "82", "source_name": "current density", "target_name": "insertion loss", "weight": 2.0, "year": 2021}, {"source": "2", "target": "83", "source_name": "current density", "target_name": "permanent magnet", "weight": 5.0, "year": 2021}, {"source": "2", "target": "86", "source_name": "current density", "target_name": "induction motor", "weight": 1.0, "year": 2021}, {"source": "2", "target": "88", "source_name": "current density", "target_name": "energy storage", "weight": 4.0, "year": 2021}, {"source": "2", "target": "90", "source_name": "current density", "target_name": "cooper pair", "weight": 2.0, "year": 2021}, {"source": "3", "target": "9", "source_name": "charge density waves", "target_name": "condensed matter physics", "weight": 2.0, "year": 2021}, {"source": "3", "target": "11", "source_name": "charge density waves", "target_name": "yttrium barium copper oxide", "weight": 1.0, "year": 2021}, {"source": "3", "target": "20", "source_name": "charge density waves", "target_name": "specific heat", "weight": 1.0, "year": 2021}, {"source": "3", "target": "23", "source_name": "charge density waves", "target_name": "order parameter", "weight": 1.0, "year": 2021}, {"source": "3", "target": "31", "source_name": "charge density waves", "target_name": "condensed matter", "weight": 2.0, "year": 2021}, {"source": "3", "target": "37", "source_name": "charge density waves", "target_name": "fermi surface", "weight": 2.0, "year": 2021}, {"source": "3", "target": "40", "source_name": "charge density waves", "target_name": "magnetic field", "weight": 2.0, "year": 2021}, {"source": "3", "target": "44", "source_name": "charge density waves", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "3", "target": "49", "source_name": "charge density waves", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "3", "target": "55", "source_name": "charge density waves", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "3", "target": "58", "source_name": "charge density waves", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "3", "target": "65", "source_name": "charge density waves", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "3", "target": "73", "source_name": "charge density waves", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "3", "target": "84", "source_name": "charge density waves", "target_name": "ground state", "weight": 2.0, "year": 2021}, {"source": "3", "target": "90", "source_name": "charge density waves", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "4", "target": "14", "source_name": "penetration depth", "target_name": "iron selenide", "weight": 1.0, "year": 2021}, {"source": "4", "target": "17", "source_name": "penetration depth", "target_name": "molecular beam epitaxy", "weight": 1.0, "year": 2021}, {"source": "4", "target": "19", "source_name": "penetration depth", "target_name": "electric field", "weight": 1.0, "year": 2021}, {"source": "4", "target": "20", "source_name": "penetration depth", "target_name": "specific heat", "weight": 2.0, "year": 2021}, {"source": "4", "target": "26", "source_name": "penetration depth", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2021}, {"source": "4", "target": "28", "source_name": "penetration depth", "target_name": "bcs theory", "weight": 2.0, "year": 2021}, {"source": "4", "target": "40", "source_name": "penetration depth", "target_name": "magnetic field", "weight": 5.0, "year": 2021}, {"source": "4", "target": "43", "source_name": "penetration depth", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2021}, {"source": "4", "target": "44", "source_name": "penetration depth", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "4", "target": "47", "source_name": "penetration depth", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "4", "target": "52", "source_name": "penetration depth", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2021}, {"source": "4", "target": "54", "source_name": "penetration depth", "target_name": "coherence length", "weight": 2.0, "year": 2021}, {"source": "4", "target": "55", "source_name": "penetration depth", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "4", "target": "57", "source_name": "penetration depth", "target_name": "density functional theory", "weight": 1.0, "year": 2021}, {"source": "4", "target": "58", "source_name": "penetration depth", "target_name": "single crystal", "weight": 2.0, "year": 2021}, {"source": "4", "target": "68", "source_name": "penetration depth", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2021}, {"source": "4", "target": "70", "source_name": "penetration depth", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "4", "target": "73", "source_name": "penetration depth", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "4", "target": "78", "source_name": "penetration depth", "target_name": "charge carrier", "weight": 2.0, "year": 2021}, {"source": "4", "target": "79", "source_name": "penetration depth", "target_name": "crystal structure", "weight": 3.0, "year": 2021}, {"source": "5", "target": "23", "source_name": "chemical vapor deposition", "target_name": "order parameter", "weight": 1.0, "year": 2021}, {"source": "5", "target": "36", "source_name": "chemical vapor deposition", "target_name": "ion beam", "weight": 1.0, "year": 2021}, {"source": "5", "target": "40", "source_name": "chemical vapor deposition", "target_name": "magnetic field", "weight": 1.0, "year": 2021}, {"source": "5", "target": "88", "source_name": "chemical vapor deposition", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "6", "target": "9", "source_name": "brillouin zone", "target_name": "condensed matter physics", "weight": 2.0, "year": 2021}, {"source": "6", "target": "10", "source_name": "brillouin zone", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2021}, {"source": "6", "target": "22", "source_name": "brillouin zone", "target_name": "unit cell", "weight": 2.0, "year": 2021}, {"source": "6", "target": "23", "source_name": "brillouin zone", "target_name": "order parameter", "weight": 3.0, "year": 2021}, {"source": "6", "target": "29", "source_name": "brillouin zone", "target_name": "raman scattering", "weight": 4.0, "year": 2021}, {"source": "6", "target": "31", "source_name": "brillouin zone", "target_name": "condensed matter", "weight": 2.0, "year": 2021}, {"source": "6", "target": "34", "source_name": "brillouin zone", "target_name": "exchange interaction", "weight": 1.0, "year": 2021}, {"source": "6", "target": "37", "source_name": "brillouin zone", "target_name": "fermi surface", "weight": 6.0, "year": 2021}, {"source": "6", "target": "44", "source_name": "brillouin zone", "target_name": "phase diagram", "weight": 4.0, "year": 2021}, {"source": "6", "target": "53", "source_name": "brillouin zone", "target_name": "spectral weight", "weight": 1.0, "year": 2021}, {"source": "6", "target": "54", "source_name": "brillouin zone", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "6", "target": "56", "source_name": "brillouin zone", "target_name": "hubbard model", "weight": 4.0, "year": 2021}, {"source": "6", "target": "57", "source_name": "brillouin zone", "target_name": "density functional theory", "weight": 1.0, "year": 2021}, {"source": "6", "target": "79", "source_name": "brillouin zone", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "6", "target": "90", "source_name": "brillouin zone", "target_name": "cooper pair", "weight": 3.0, "year": 2021}, {"source": "7", "target": "16", "source_name": "kinetic energy", "target_name": "coulomb repulsion", "weight": 4.0, "year": 2021}, {"source": "7", "target": "28", "source_name": "kinetic energy", "target_name": "bcs theory", "weight": 2.0, "year": 2021}, {"source": "7", "target": "32", "source_name": "kinetic energy", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2021}, {"source": "7", "target": "37", "source_name": "kinetic energy", "target_name": "fermi surface", "weight": 2.0, "year": 2021}, {"source": "7", "target": "40", "source_name": "kinetic energy", "target_name": "magnetic field", "weight": 1.0, "year": 2021}, {"source": "7", "target": "44", "source_name": "kinetic energy", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "7", "target": "48", "source_name": "kinetic energy", "target_name": "neutron scattering", "weight": 1.0, "year": 2021}, {"source": "7", "target": "49", "source_name": "kinetic energy", "target_name": "strongly correlated", "weight": 6.0, "year": 2021}, {"source": "7", "target": "53", "source_name": "kinetic energy", "target_name": "spectral weight", "weight": 1.0, "year": 2021}, {"source": "7", "target": "54", "source_name": "kinetic energy", "target_name": "coherence length", "weight": 2.0, "year": 2021}, {"source": "7", "target": "55", "source_name": "kinetic energy", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "7", "target": "56", "source_name": "kinetic energy", "target_name": "hubbard model", "weight": 5.0, "year": 2021}, {"source": "7", "target": "59", "source_name": "kinetic energy", "target_name": "monte carlo", "weight": 2.0, "year": 2021}, {"source": "7", "target": "65", "source_name": "kinetic energy", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "7", "target": "77", "source_name": "kinetic energy", "target_name": "magnetic levitation", "weight": 1.0, "year": 2021}, {"source": "7", "target": "78", "source_name": "kinetic energy", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "7", "target": "83", "source_name": "kinetic energy", "target_name": "permanent magnet", "weight": 1.0, "year": 2021}, {"source": "7", "target": "88", "source_name": "kinetic energy", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "8", "target": "22", "source_name": "symmetry breaking", "target_name": "unit cell", "weight": 1.0, "year": 2021}, {"source": "8", "target": "23", "source_name": "symmetry breaking", "target_name": "order parameter", "weight": 1.0, "year": 2021}, {"source": "8", "target": "28", "source_name": "symmetry breaking", "target_name": "bcs theory", "weight": 1.0, "year": 2021}, {"source": "8", "target": "49", "source_name": "symmetry breaking", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "9", "target": "10", "source_name": "condensed matter physics", "target_name": "liquid nitrogen", "weight": 1.0, "year": 2021}, {"source": "9", "target": "17", "source_name": "condensed matter physics", "target_name": "molecular beam epitaxy", "weight": 4.0, "year": 2021}, {"source": "9", "target": "22", "source_name": "condensed matter physics", "target_name": "unit cell", "weight": 3.0, "year": 2021}, {"source": "9", "target": "23", "source_name": "condensed matter physics", "target_name": "order parameter", "weight": 3.0, "year": 2021}, {"source": "9", "target": "30", "source_name": "condensed matter physics", "target_name": "fermi level", "weight": 2.0, "year": 2021}, {"source": "9", "target": "31", "source_name": "condensed matter physics", "target_name": "condensed matter", "weight": 24.0, "year": 2021}, {"source": "9", "target": "37", "source_name": "condensed matter physics", "target_name": "fermi surface", "weight": 2.0, "year": 2021}, {"source": "9", "target": "40", "source_name": "condensed matter physics", "target_name": "magnetic field", "weight": 3.0, "year": 2021}, {"source": "9", "target": "44", "source_name": "condensed matter physics", "target_name": "phase diagram", "weight": 3.0, "year": 2021}, {"source": "9", "target": "46", "source_name": "condensed matter physics", "target_name": "iron pnictides", "weight": 1.0, "year": 2021}, {"source": "9", "target": "48", "source_name": "condensed matter physics", "target_name": "neutron scattering", "weight": 4.0, "year": 2021}, {"source": "9", "target": "49", "source_name": "condensed matter physics", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "9", "target": "53", "source_name": "condensed matter physics", "target_name": "spectral weight", "weight": 3.0, "year": 2021}, {"source": "9", "target": "55", "source_name": "condensed matter physics", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "9", "target": "58", "source_name": "condensed matter physics", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "9", "target": "60", "source_name": "condensed matter physics", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "9", "target": "64", "source_name": "condensed matter physics", "target_name": "liquid helium", "weight": 1.0, "year": 2021}, {"source": "9", "target": "65", "source_name": "condensed matter physics", "target_name": "copper oxide", "weight": 3.0, "year": 2021}, {"source": "9", "target": "73", "source_name": "condensed matter physics", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "9", "target": "78", "source_name": "condensed matter physics", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "9", "target": "79", "source_name": "condensed matter physics", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "9", "target": "84", "source_name": "condensed matter physics", "target_name": "ground state", "weight": 5.0, "year": 2021}, {"source": "9", "target": "87", "source_name": "condensed matter physics", "target_name": "charge transfer", "weight": 4.0, "year": 2021}, {"source": "9", "target": "90", "source_name": "condensed matter physics", "target_name": "cooper pair", "weight": 4.0, "year": 2021}, {"source": "10", "target": "11", "source_name": "liquid nitrogen", "target_name": "yttrium barium copper oxide", "weight": 2.0, "year": 2021}, {"source": "10", "target": "13", "source_name": "liquid nitrogen", "target_name": "josephson junctions", "weight": 1.0, "year": 2021}, {"source": "10", "target": "14", "source_name": "liquid nitrogen", "target_name": "iron selenide", "weight": 1.0, "year": 2021}, {"source": "10", "target": "15", "source_name": "liquid nitrogen", "target_name": "magnetic flux", "weight": 1.0, "year": 2021}, {"source": "10", "target": "19", "source_name": "liquid nitrogen", "target_name": "electric field", "weight": 2.0, "year": 2021}, {"source": "10", "target": "20", "source_name": "liquid nitrogen", "target_name": "specific heat", "weight": 1.0, "year": 2021}, {"source": "10", "target": "21", "source_name": "liquid nitrogen", "target_name": "grain boundary", "weight": 1.0, "year": 2021}, {"source": "10", "target": "22", "source_name": "liquid nitrogen", "target_name": "unit cell", "weight": 2.0, "year": 2021}, {"source": "10", "target": "24", "source_name": "liquid nitrogen", "target_name": "magnetic resonance imaging", "weight": 2.0, "year": 2021}, {"source": "10", "target": "27", "source_name": "liquid nitrogen", "target_name": "ac losses", "weight": 1.0, "year": 2021}, {"source": "10", "target": "28", "source_name": "liquid nitrogen", "target_name": "bcs theory", "weight": 1.0, "year": 2021}, {"source": "10", "target": "31", "source_name": "liquid nitrogen", "target_name": "condensed matter", "weight": 1.0, "year": 2021}, {"source": "10", "target": "33", "source_name": "liquid nitrogen", "target_name": "strontium titanate", "weight": 1.0, "year": 2021}, {"source": "10", "target": "36", "source_name": "liquid nitrogen", "target_name": "ion beam", "weight": 2.0, "year": 2021}, {"source": "10", "target": "37", "source_name": "liquid nitrogen", "target_name": "fermi surface", "weight": 2.0, "year": 2021}, {"source": "10", "target": "39", "source_name": "liquid nitrogen", "target_name": "finite element method", "weight": 1.0, "year": 2021}, {"source": "10", "target": "40", "source_name": "liquid nitrogen", "target_name": "magnetic field", "weight": 22.0, "year": 2021}, {"source": "10", "target": "41", "source_name": "liquid nitrogen", "target_name": "grain boundaries", "weight": 1.0, "year": 2021}, {"source": "10", "target": "42", "source_name": "liquid nitrogen", "target_name": "rare earth", "weight": 2.0, "year": 2021}, {"source": "10", "target": "43", "source_name": "liquid nitrogen", "target_name": "transmission electron microscopy", "weight": 1.0, "year": 2021}, {"source": "10", "target": "44", "source_name": "liquid nitrogen", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "10", "target": "45", "source_name": "liquid nitrogen", "target_name": "power transmission", "weight": 5.0, "year": 2021}, {"source": "10", "target": "47", "source_name": "liquid nitrogen", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "10", "target": "50", "source_name": "liquid nitrogen", "target_name": "coated conductor", "weight": 5.0, "year": 2021}, {"source": "10", "target": "51", "source_name": "liquid nitrogen", "target_name": "wind turbine", "weight": 1.0, "year": 2021}, {"source": "10", "target": "54", "source_name": "liquid nitrogen", "target_name": "coherence length", "weight": 3.0, "year": 2021}, {"source": "10", "target": "58", "source_name": "liquid nitrogen", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "10", "target": "61", "source_name": "liquid nitrogen", "target_name": "synchronous motor", "weight": 1.0, "year": 2021}, {"source": "10", "target": "63", "source_name": "liquid nitrogen", "target_name": "weak links", "weight": 1.0, "year": 2021}, {"source": "10", "target": "64", "source_name": "liquid nitrogen", "target_name": "liquid helium", "weight": 7.0, "year": 2021}, {"source": "10", "target": "65", "source_name": "liquid nitrogen", "target_name": "copper oxide", "weight": 2.0, "year": 2021}, {"source": "10", "target": "66", "source_name": "liquid nitrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2021}, {"source": "10", "target": "68", "source_name": "liquid nitrogen", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2021}, {"source": "10", "target": "70", "source_name": "liquid nitrogen", "target_name": "meissner effect", "weight": 2.0, "year": 2021}, {"source": "10", "target": "72", "source_name": "liquid nitrogen", "target_name": "electrical resistance", "weight": 2.0, "year": 2021}, {"source": "10", "target": "73", "source_name": "liquid nitrogen", "target_name": "room temperature", "weight": 5.0, "year": 2021}, {"source": "10", "target": "74", "source_name": "liquid nitrogen", "target_name": "transmission line", "weight": 1.0, "year": 2021}, {"source": "10", "target": "75", "source_name": "liquid nitrogen", "target_name": "stainless steel", "weight": 1.0, "year": 2021}, {"source": "10", "target": "77", "source_name": "liquid nitrogen", "target_name": "magnetic levitation", "weight": 4.0, "year": 2021}, {"source": "10", "target": "79", "source_name": "liquid nitrogen", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "10", "target": "80", "source_name": "liquid nitrogen", "target_name": "quench propagation", "weight": 1.0, "year": 2021}, {"source": "10", "target": "81", "source_name": "liquid nitrogen", "target_name": "finite element", "weight": 2.0, "year": 2021}, {"source": "10", "target": "82", "source_name": "liquid nitrogen", "target_name": "insertion loss", "weight": 3.0, "year": 2021}, {"source": "10", "target": "83", "source_name": "liquid nitrogen", "target_name": "permanent magnet", "weight": 6.0, "year": 2021}, {"source": "10", "target": "86", "source_name": "liquid nitrogen", "target_name": "induction motor", "weight": 1.0, "year": 2021}, {"source": "10", "target": "88", "source_name": "liquid nitrogen", "target_name": "energy storage", "weight": 5.0, "year": 2021}, {"source": "10", "target": "90", "source_name": "liquid nitrogen", "target_name": "cooper pair", "weight": 2.0, "year": 2021}, {"source": "10", "target": "91", "source_name": "liquid nitrogen", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "10", "target": "92", "source_name": "liquid nitrogen", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "11", "target": "13", "source_name": "yttrium barium copper oxide", "target_name": "josephson junctions", "weight": 1.0, "year": 2021}, {"source": "11", "target": "39", "source_name": "yttrium barium copper oxide", "target_name": "finite element method", "weight": 1.0, "year": 2021}, {"source": "11", "target": "40", "source_name": "yttrium barium copper oxide", "target_name": "magnetic field", "weight": 3.0, "year": 2021}, {"source": "11", "target": "46", "source_name": "yttrium barium copper oxide", "target_name": "iron pnictides", "weight": 1.0, "year": 2021}, {"source": "11", "target": "51", "source_name": "yttrium barium copper oxide", "target_name": "wind turbine", "weight": 1.0, "year": 2021}, {"source": "11", "target": "54", "source_name": "yttrium barium copper oxide", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "11", "target": "58", "source_name": "yttrium barium copper oxide", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "11", "target": "65", "source_name": "yttrium barium copper oxide", "target_name": "copper oxide", "weight": 11.0, "year": 2021}, {"source": "11", "target": "67", "source_name": "yttrium barium copper oxide", "target_name": "magnesium diboride", "weight": 1.0, "year": 2021}, {"source": "11", "target": "73", "source_name": "yttrium barium copper oxide", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "11", "target": "79", "source_name": "yttrium barium copper oxide", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "11", "target": "81", "source_name": "yttrium barium copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "11", "target": "88", "source_name": "yttrium barium copper oxide", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "11", "target": "90", "source_name": "yttrium barium copper oxide", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "12", "target": "17", "source_name": "scanning tunneling microscopy", "target_name": "molecular beam epitaxy", "weight": 6.0, "year": 2021}, {"source": "12", "target": "19", "source_name": "scanning tunneling microscopy", "target_name": "electric field", "weight": 2.0, "year": 2021}, {"source": "12", "target": "20", "source_name": "scanning tunneling microscopy", "target_name": "specific heat", "weight": 1.0, "year": 2021}, {"source": "12", "target": "22", "source_name": "scanning tunneling microscopy", "target_name": "unit cell", "weight": 5.0, "year": 2021}, {"source": "12", "target": "40", "source_name": "scanning tunneling microscopy", "target_name": "magnetic field", "weight": 6.0, "year": 2021}, {"source": "12", "target": "44", "source_name": "scanning tunneling microscopy", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "12", "target": "49", "source_name": "scanning tunneling microscopy", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "12", "target": "55", "source_name": "scanning tunneling microscopy", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "12", "target": "56", "source_name": "scanning tunneling microscopy", "target_name": "hubbard model", "weight": 1.0, "year": 2021}, {"source": "12", "target": "58", "source_name": "scanning tunneling microscopy", "target_name": "single crystal", "weight": 3.0, "year": 2021}, {"source": "12", "target": "59", "source_name": "scanning tunneling microscopy", "target_name": "monte carlo", "weight": 1.0, "year": 2021}, {"source": "12", "target": "60", "source_name": "scanning tunneling microscopy", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "12", "target": "84", "source_name": "scanning tunneling microscopy", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "12", "target": "87", "source_name": "scanning tunneling microscopy", "target_name": "charge transfer", "weight": 3.0, "year": 2021}, {"source": "13", "target": "20", "source_name": "josephson junctions", "target_name": "specific heat", "weight": 1.0, "year": 2021}, {"source": "13", "target": "21", "source_name": "josephson junctions", "target_name": "grain boundary", "weight": 1.0, "year": 2021}, {"source": "13", "target": "23", "source_name": "josephson junctions", "target_name": "order parameter", "weight": 1.0, "year": 2021}, {"source": "13", "target": "36", "source_name": "josephson junctions", "target_name": "ion beam", "weight": 4.0, "year": 2021}, {"source": "13", "target": "40", "source_name": "josephson junctions", "target_name": "magnetic field", "weight": 2.0, "year": 2021}, {"source": "13", "target": "41", "source_name": "josephson junctions", "target_name": "grain boundaries", "weight": 1.0, "year": 2021}, {"source": "13", "target": "44", "source_name": "josephson junctions", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "13", "target": "49", "source_name": "josephson junctions", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "13", "target": "54", "source_name": "josephson junctions", "target_name": "coherence length", "weight": 3.0, "year": 2021}, {"source": "13", "target": "56", "source_name": "josephson junctions", "target_name": "hubbard model", "weight": 1.0, "year": 2021}, {"source": "13", "target": "58", "source_name": "josephson junctions", "target_name": "single crystal", "weight": 4.0, "year": 2021}, {"source": "13", "target": "63", "source_name": "josephson junctions", "target_name": "weak links", "weight": 1.0, "year": 2021}, {"source": "13", "target": "65", "source_name": "josephson junctions", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "13", "target": "67", "source_name": "josephson junctions", "target_name": "magnesium diboride", "weight": 2.0, "year": 2021}, {"source": "13", "target": "73", "source_name": "josephson junctions", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "13", "target": "81", "source_name": "josephson junctions", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "13", "target": "90", "source_name": "josephson junctions", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "14", "target": "20", "source_name": "iron selenide", "target_name": "specific heat", "weight": 1.0, "year": 2021}, {"source": "14", "target": "22", "source_name": "iron selenide", "target_name": "unit cell", "weight": 1.0, "year": 2021}, {"source": "14", "target": "28", "source_name": "iron selenide", "target_name": "bcs theory", "weight": 1.0, "year": 2021}, {"source": "14", "target": "33", "source_name": "iron selenide", "target_name": "strontium titanate", "weight": 3.0, "year": 2021}, {"source": "14", "target": "34", "source_name": "iron selenide", "target_name": "exchange interaction", "weight": 1.0, "year": 2021}, {"source": "14", "target": "40", "source_name": "iron selenide", "target_name": "magnetic field", "weight": 2.0, "year": 2021}, {"source": "14", "target": "47", "source_name": "iron selenide", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "14", "target": "58", "source_name": "iron selenide", "target_name": "single crystal", "weight": 2.0, "year": 2021}, {"source": "14", "target": "90", "source_name": "iron selenide", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "15", "target": "19", "source_name": "magnetic flux", "target_name": "electric field", "weight": 1.0, "year": 2021}, {"source": "15", "target": "20", "source_name": "magnetic flux", "target_name": "specific heat", "weight": 1.0, "year": 2021}, {"source": "15", "target": "23", "source_name": "magnetic flux", "target_name": "order parameter", "weight": 1.0, "year": 2021}, {"source": "15", "target": "32", "source_name": "magnetic flux", "target_name": "flywheel energy storage", "weight": 1.0, "year": 2021}, {"source": "15", "target": "39", "source_name": "magnetic flux", "target_name": "finite element method", "weight": 1.0, "year": 2021}, {"source": "15", "target": "40", "source_name": "magnetic flux", "target_name": "magnetic field", "weight": 12.0, "year": 2021}, {"source": "15", "target": "41", "source_name": "magnetic flux", "target_name": "grain boundaries", "weight": 1.0, "year": 2021}, {"source": "15", "target": "50", "source_name": "magnetic flux", "target_name": "coated conductor", "weight": 3.0, "year": 2021}, {"source": "15", "target": "61", "source_name": "magnetic flux", "target_name": "synchronous motor", "weight": 2.0, "year": 2021}, {"source": "15", "target": "64", "source_name": "magnetic flux", "target_name": "liquid helium", "weight": 3.0, "year": 2021}, {"source": "15", "target": "65", "source_name": "magnetic flux", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "15", "target": "67", "source_name": "magnetic flux", "target_name": "magnesium diboride", "weight": 1.0, "year": 2021}, {"source": "15", "target": "73", "source_name": "magnetic flux", "target_name": "room temperature", "weight": 2.0, "year": 2021}, {"source": "15", "target": "78", "source_name": "magnetic flux", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "15", "target": "83", "source_name": "magnetic flux", "target_name": "permanent magnet", "weight": 1.0, "year": 2021}, {"source": "15", "target": "88", "source_name": "magnetic flux", "target_name": "energy storage", "weight": 2.0, "year": 2021}, {"source": "15", "target": "90", "source_name": "magnetic flux", "target_name": "cooper pair", "weight": 2.0, "year": 2021}, {"source": "16", "target": "20", "source_name": "coulomb repulsion", "target_name": "specific heat", "weight": 2.0, "year": 2021}, {"source": "16", "target": "23", "source_name": "coulomb repulsion", "target_name": "order parameter", "weight": 2.0, "year": 2021}, {"source": "16", "target": "28", "source_name": "coulomb repulsion", "target_name": "bcs theory", "weight": 3.0, "year": 2021}, {"source": "16", "target": "34", "source_name": "coulomb repulsion", "target_name": "exchange interaction", "weight": 4.0, "year": 2021}, {"source": "16", "target": "37", "source_name": "coulomb repulsion", "target_name": "fermi surface", "weight": 2.0, "year": 2021}, {"source": "16", "target": "40", "source_name": "coulomb repulsion", "target_name": "magnetic field", "weight": 1.0, "year": 2021}, {"source": "16", "target": "44", "source_name": "coulomb repulsion", "target_name": "phase diagram", "weight": 2.0, "year": 2021}, {"source": "16", "target": "47", "source_name": "coulomb repulsion", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "16", "target": "49", "source_name": "coulomb repulsion", "target_name": "strongly correlated", "weight": 7.0, "year": 2021}, {"source": "16", "target": "55", "source_name": "coulomb repulsion", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "16", "target": "56", "source_name": "coulomb repulsion", "target_name": "hubbard model", "weight": 6.0, "year": 2021}, {"source": "16", "target": "57", "source_name": "coulomb repulsion", "target_name": "density functional theory", "weight": 1.0, "year": 2021}, {"source": "16", "target": "59", "source_name": "coulomb repulsion", "target_name": "monte carlo", "weight": 3.0, "year": 2021}, {"source": "16", "target": "60", "source_name": "coulomb repulsion", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "16", "target": "72", "source_name": "coulomb repulsion", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "16", "target": "78", "source_name": "coulomb repulsion", "target_name": "charge carrier", "weight": 2.0, "year": 2021}, {"source": "16", "target": "85", "source_name": "coulomb repulsion", "target_name": "perturbation theory", "weight": 1.0, "year": 2021}, {"source": "16", "target": "90", "source_name": "coulomb repulsion", "target_name": "cooper pair", "weight": 3.0, "year": 2021}, {"source": "16", "target": "92", "source_name": "coulomb repulsion", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "17", "target": "19", "source_name": "molecular beam epitaxy", "target_name": "electric field", "weight": 3.0, "year": 2021}, {"source": "17", "target": "22", "source_name": "molecular beam epitaxy", "target_name": "unit cell", "weight": 5.0, "year": 2021}, {"source": "17", "target": "31", "source_name": "molecular beam epitaxy", "target_name": "condensed matter", "weight": 4.0, "year": 2021}, {"source": "17", "target": "40", "source_name": "molecular beam epitaxy", "target_name": "magnetic field", "weight": 8.0, "year": 2021}, {"source": "17", "target": "43", "source_name": "molecular beam epitaxy", "target_name": "transmission electron microscopy", "weight": 2.0, "year": 2021}, {"source": "17", "target": "54", "source_name": "molecular beam epitaxy", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "17", "target": "58", "source_name": "molecular beam epitaxy", "target_name": "single crystal", "weight": 4.0, "year": 2021}, {"source": "17", "target": "65", "source_name": "molecular beam epitaxy", "target_name": "copper oxide", "weight": 3.0, "year": 2021}, {"source": "17", "target": "70", "source_name": "molecular beam epitaxy", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "17", "target": "73", "source_name": "molecular beam epitaxy", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "17", "target": "78", "source_name": "molecular beam epitaxy", "target_name": "charge carrier", "weight": 2.0, "year": 2021}, {"source": "17", "target": "87", "source_name": "molecular beam epitaxy", "target_name": "charge transfer", "weight": 6.0, "year": 2021}, {"source": "17", "target": "90", "source_name": "molecular beam epitaxy", "target_name": "cooper pair", "weight": 5.0, "year": 2021}, {"source": "18", "target": "20", "source_name": "fermi arcs", "target_name": "specific heat", "weight": 7.0, "year": 2021}, {"source": "18", "target": "28", "source_name": "fermi arcs", "target_name": "bcs theory", "weight": 3.0, "year": 2021}, {"source": "18", "target": "30", "source_name": "fermi arcs", "target_name": "fermi level", "weight": 1.0, "year": 2021}, {"source": "18", "target": "37", "source_name": "fermi arcs", "target_name": "fermi surface", "weight": 1.0, "year": 2021}, {"source": "18", "target": "40", "source_name": "fermi arcs", "target_name": "magnetic field", "weight": 7.0, "year": 2021}, {"source": "18", "target": "44", "source_name": "fermi arcs", "target_name": "phase diagram", "weight": 2.0, "year": 2021}, {"source": "18", "target": "65", "source_name": "fermi arcs", "target_name": "copper oxide", "weight": 7.0, "year": 2021}, {"source": "19", "target": "20", "source_name": "electric field", "target_name": "specific heat", "weight": 1.0, "year": 2021}, {"source": "19", "target": "33", "source_name": "electric field", "target_name": "strontium titanate", "weight": 1.0, "year": 2021}, {"source": "19", "target": "40", "source_name": "electric field", "target_name": "magnetic field", "weight": 11.0, "year": 2021}, {"source": "19", "target": "47", "source_name": "electric field", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "19", "target": "50", "source_name": "electric field", "target_name": "coated conductor", "weight": 1.0, "year": 2021}, {"source": "19", "target": "57", "source_name": "electric field", "target_name": "density functional theory", "weight": 1.0, "year": 2021}, {"source": "19", "target": "58", "source_name": "electric field", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "19", "target": "65", "source_name": "electric field", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "19", "target": "71", "source_name": "electric field", "target_name": "van hove", "weight": 1.0, "year": 2021}, {"source": "19", "target": "73", "source_name": "electric field", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "19", "target": "78", "source_name": "electric field", "target_name": "charge carrier", "weight": 3.0, "year": 2021}, {"source": "19", "target": "87", "source_name": "electric field", "target_name": "charge transfer", "weight": 1.0, "year": 2021}, {"source": "19", "target": "91", "source_name": "electric field", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "19", "target": "92", "source_name": "electric field", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "20", "target": "22", "source_name": "specific heat", "target_name": "unit cell", "weight": 1.0, "year": 2021}, {"source": "20", "target": "23", "source_name": "specific heat", "target_name": "order parameter", "weight": 3.0, "year": 2021}, {"source": "20", "target": "28", "source_name": "specific heat", "target_name": "bcs theory", "weight": 4.0, "year": 2021}, {"source": "20", "target": "30", "source_name": "specific heat", "target_name": "fermi level", "weight": 8.0, "year": 2021}, {"source": "20", "target": "35", "source_name": "specific heat", "target_name": "space group", "weight": 3.0, "year": 2021}, {"source": "20", "target": "37", "source_name": "specific heat", "target_name": "fermi surface", "weight": 4.0, "year": 2021}, {"source": "20", "target": "40", "source_name": "specific heat", "target_name": "magnetic field", "weight": 13.0, "year": 2021}, {"source": "20", "target": "42", "source_name": "specific heat", "target_name": "rare earth", "weight": 1.0, "year": 2021}, {"source": "20", "target": "44", "source_name": "specific heat", "target_name": "phase diagram", "weight": 7.0, "year": 2021}, {"source": "20", "target": "47", "source_name": "specific heat", "target_name": "magnetic susceptibility", "weight": 6.0, "year": 2021}, {"source": "20", "target": "49", "source_name": "specific heat", "target_name": "strongly correlated", "weight": 3.0, "year": 2021}, {"source": "20", "target": "52", "source_name": "specific heat", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2021}, {"source": "20", "target": "54", "source_name": "specific heat", "target_name": "coherence length", "weight": 2.0, "year": 2021}, {"source": "20", "target": "55", "source_name": "specific heat", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "20", "target": "56", "source_name": "specific heat", "target_name": "hubbard model", "weight": 2.0, "year": 2021}, {"source": "20", "target": "57", "source_name": "specific heat", "target_name": "density functional theory", "weight": 1.0, "year": 2021}, {"source": "20", "target": "58", "source_name": "specific heat", "target_name": "single crystal", "weight": 11.0, "year": 2021}, {"source": "20", "target": "65", "source_name": "specific heat", "target_name": "copper oxide", "weight": 7.0, "year": 2021}, {"source": "20", "target": "73", "source_name": "specific heat", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "20", "target": "78", "source_name": "specific heat", "target_name": "charge carrier", "weight": 3.0, "year": 2021}, {"source": "20", "target": "79", "source_name": "specific heat", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "20", "target": "84", "source_name": "specific heat", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "20", "target": "85", "source_name": "specific heat", "target_name": "perturbation theory", "weight": 1.0, "year": 2021}, {"source": "20", "target": "90", "source_name": "specific heat", "target_name": "cooper pair", "weight": 2.0, "year": 2021}, {"source": "20", "target": "91", "source_name": "specific heat", "target_name": "heat capacity", "weight": 6.0, "year": 2021}, {"source": "20", "target": "92", "source_name": "specific heat", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "21", "target": "41", "source_name": "grain boundary", "target_name": "grain boundaries", "weight": 3.0, "year": 2021}, {"source": "21", "target": "42", "source_name": "grain boundary", "target_name": "rare earth", "weight": 1.0, "year": 2021}, {"source": "21", "target": "44", "source_name": "grain boundary", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "21", "target": "46", "source_name": "grain boundary", "target_name": "iron pnictides", "weight": 1.0, "year": 2021}, {"source": "21", "target": "58", "source_name": "grain boundary", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "21", "target": "65", "source_name": "grain boundary", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "22", "target": "28", "source_name": "unit cell", "target_name": "bcs theory", "weight": 1.0, "year": 2021}, {"source": "22", "target": "31", "source_name": "unit cell", "target_name": "condensed matter", "weight": 3.0, "year": 2021}, {"source": "22", "target": "33", "source_name": "unit cell", "target_name": "strontium titanate", "weight": 1.0, "year": 2021}, {"source": "22", "target": "37", "source_name": "unit cell", "target_name": "fermi surface", "weight": 1.0, "year": 2021}, {"source": "22", "target": "40", "source_name": "unit cell", "target_name": "magnetic field", "weight": 4.0, "year": 2021}, {"source": "22", "target": "44", "source_name": "unit cell", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "22", "target": "49", "source_name": "unit cell", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "22", "target": "54", "source_name": "unit cell", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "22", "target": "55", "source_name": "unit cell", "target_name": "optimally doped", "weight": 2.0, "year": 2021}, {"source": "22", "target": "57", "source_name": "unit cell", "target_name": "density functional theory", "weight": 3.0, "year": 2021}, {"source": "22", "target": "58", "source_name": "unit cell", "target_name": "single crystal", "weight": 3.0, "year": 2021}, {"source": "22", "target": "65", "source_name": "unit cell", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "22", "target": "70", "source_name": "unit cell", "target_name": "meissner effect", "weight": 2.0, "year": 2021}, {"source": "22", "target": "73", "source_name": "unit cell", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "22", "target": "79", "source_name": "unit cell", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "22", "target": "84", "source_name": "unit cell", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "22", "target": "87", "source_name": "unit cell", "target_name": "charge transfer", "weight": 2.0, "year": 2021}, {"source": "23", "target": "26", "source_name": "order parameter", "target_name": "carbon nanotubes", "weight": 1.0, "year": 2021}, {"source": "23", "target": "28", "source_name": "order parameter", "target_name": "bcs theory", "weight": 1.0, "year": 2021}, {"source": "23", "target": "29", "source_name": "order parameter", "target_name": "raman scattering", "weight": 3.0, "year": 2021}, {"source": "23", "target": "31", "source_name": "order parameter", "target_name": "condensed matter", "weight": 2.0, "year": 2021}, {"source": "23", "target": "37", "source_name": "order parameter", "target_name": "fermi surface", "weight": 9.0, "year": 2021}, {"source": "23", "target": "38", "source_name": "order parameter", "target_name": "metallic hydrogen", "weight": 2.0, "year": 2021}, {"source": "23", "target": "40", "source_name": "order parameter", "target_name": "magnetic field", "weight": 6.0, "year": 2021}, {"source": "23", "target": "41", "source_name": "order parameter", "target_name": "grain boundaries", "weight": 1.0, "year": 2021}, {"source": "23", "target": "44", "source_name": "order parameter", "target_name": "phase diagram", "weight": 5.0, "year": 2021}, {"source": "23", "target": "46", "source_name": "order parameter", "target_name": "iron pnictides", "weight": 4.0, "year": 2021}, {"source": "23", "target": "47", "source_name": "order parameter", "target_name": "magnetic susceptibility", "weight": 2.0, "year": 2021}, {"source": "23", "target": "48", "source_name": "order parameter", "target_name": "neutron scattering", "weight": 2.0, "year": 2021}, {"source": "23", "target": "49", "source_name": "order parameter", "target_name": "strongly correlated", "weight": 3.0, "year": 2021}, {"source": "23", "target": "53", "source_name": "order parameter", "target_name": "spectral weight", "weight": 2.0, "year": 2021}, {"source": "23", "target": "54", "source_name": "order parameter", "target_name": "coherence length", "weight": 3.0, "year": 2021}, {"source": "23", "target": "55", "source_name": "order parameter", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "23", "target": "56", "source_name": "order parameter", "target_name": "hubbard model", "weight": 8.0, "year": 2021}, {"source": "23", "target": "58", "source_name": "order parameter", "target_name": "single crystal", "weight": 2.0, "year": 2021}, {"source": "23", "target": "59", "source_name": "order parameter", "target_name": "monte carlo", "weight": 2.0, "year": 2021}, {"source": "23", "target": "60", "source_name": "order parameter", "target_name": "mott insulator", "weight": 2.0, "year": 2021}, {"source": "23", "target": "63", "source_name": "order parameter", "target_name": "weak links", "weight": 1.0, "year": 2021}, {"source": "23", "target": "65", "source_name": "order parameter", "target_name": "copper oxide", "weight": 5.0, "year": 2021}, {"source": "23", "target": "71", "source_name": "order parameter", "target_name": "van hove", "weight": 1.0, "year": 2021}, {"source": "23", "target": "73", "source_name": "order parameter", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "23", "target": "84", "source_name": "order parameter", "target_name": "ground state", "weight": 2.0, "year": 2021}, {"source": "23", "target": "85", "source_name": "order parameter", "target_name": "perturbation theory", "weight": 3.0, "year": 2021}, {"source": "23", "target": "88", "source_name": "order parameter", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "23", "target": "90", "source_name": "order parameter", "target_name": "cooper pair", "weight": 6.0, "year": 2021}, {"source": "24", "target": "40", "source_name": "magnetic resonance imaging", "target_name": "magnetic field", "weight": 4.0, "year": 2021}, {"source": "24", "target": "45", "source_name": "magnetic resonance imaging", "target_name": "power transmission", "weight": 1.0, "year": 2021}, {"source": "24", "target": "50", "source_name": "magnetic resonance imaging", "target_name": "coated conductor", "weight": 2.0, "year": 2021}, {"source": "24", "target": "54", "source_name": "magnetic resonance imaging", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "24", "target": "64", "source_name": "magnetic resonance imaging", "target_name": "liquid helium", "weight": 1.0, "year": 2021}, {"source": "24", "target": "68", "source_name": "magnetic resonance imaging", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2021}, {"source": "24", "target": "72", "source_name": "magnetic resonance imaging", "target_name": "electrical resistance", "weight": 2.0, "year": 2021}, {"source": "24", "target": "77", "source_name": "magnetic resonance imaging", "target_name": "magnetic levitation", "weight": 3.0, "year": 2021}, {"source": "24", "target": "88", "source_name": "magnetic resonance imaging", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "25", "target": "73", "source_name": "short circuit", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "26", "target": "30", "source_name": "carbon nanotubes", "target_name": "fermi level", "weight": 1.0, "year": 2021}, {"source": "26", "target": "31", "source_name": "carbon nanotubes", "target_name": "condensed matter", "weight": 1.0, "year": 2021}, {"source": "26", "target": "44", "source_name": "carbon nanotubes", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "26", "target": "47", "source_name": "carbon nanotubes", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "26", "target": "70", "source_name": "carbon nanotubes", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "26", "target": "71", "source_name": "carbon nanotubes", "target_name": "van hove", "weight": 1.0, "year": 2021}, {"source": "26", "target": "73", "source_name": "carbon nanotubes", "target_name": "room temperature", "weight": 2.0, "year": 2021}, {"source": "26", "target": "90", "source_name": "carbon nanotubes", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "27", "target": "39", "source_name": "ac losses", "target_name": "finite element method", "weight": 1.0, "year": 2021}, {"source": "27", "target": "40", "source_name": "ac losses", "target_name": "magnetic field", "weight": 6.0, "year": 2021}, {"source": "27", "target": "44", "source_name": "ac losses", "target_name": "phase diagram", "weight": 1.0, "year": 2021}, {"source": "27", "target": "45", "source_name": "ac losses", "target_name": "power transmission", "weight": 1.0, "year": 2021}, {"source": "27", "target": "50", "source_name": "ac losses", "target_name": "coated conductor", "weight": 1.0, "year": 2021}, {"source": "27", "target": "51", "source_name": "ac losses", "target_name": "wind turbine", "weight": 1.0, "year": 2021}, {"source": "27", "target": "61", "source_name": "ac losses", "target_name": "synchronous motor", "weight": 1.0, "year": 2021}, {"source": "27", "target": "62", "source_name": "ac losses", "target_name": "alternating current", "weight": 1.0, "year": 2021}, {"source": "27", "target": "63", "source_name": "ac losses", "target_name": "weak links", "weight": 1.0, "year": 2021}, {"source": "27", "target": "74", "source_name": "ac losses", "target_name": "transmission line", "weight": 1.0, "year": 2021}, {"source": "27", "target": "81", "source_name": "ac losses", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "27", "target": "86", "source_name": "ac losses", "target_name": "induction motor", "weight": 1.0, "year": 2021}, {"source": "27", "target": "88", "source_name": "ac losses", "target_name": "energy storage", "weight": 2.0, "year": 2021}, {"source": "28", "target": "30", "source_name": "bcs theory", "target_name": "fermi level", "weight": 1.0, "year": 2021}, {"source": "28", "target": "37", "source_name": "bcs theory", "target_name": "fermi surface", "weight": 3.0, "year": 2021}, {"source": "28", "target": "38", "source_name": "bcs theory", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2021}, {"source": "28", "target": "40", "source_name": "bcs theory", "target_name": "magnetic field", "weight": 6.0, "year": 2021}, {"source": "28", "target": "44", "source_name": "bcs theory", "target_name": "phase diagram", "weight": 4.0, "year": 2021}, {"source": "28", "target": "46", "source_name": "bcs theory", "target_name": "iron pnictides", "weight": 1.0, "year": 2021}, {"source": "28", "target": "47", "source_name": "bcs theory", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "28", "target": "48", "source_name": "bcs theory", "target_name": "neutron scattering", "weight": 1.0, "year": 2021}, {"source": "28", "target": "49", "source_name": "bcs theory", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "28", "target": "54", "source_name": "bcs theory", "target_name": "coherence length", "weight": 3.0, "year": 2021}, {"source": "28", "target": "55", "source_name": "bcs theory", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "28", "target": "56", "source_name": "bcs theory", "target_name": "hubbard model", "weight": 1.0, "year": 2021}, {"source": "28", "target": "58", "source_name": "bcs theory", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "28", "target": "60", "source_name": "bcs theory", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "28", "target": "64", "source_name": "bcs theory", "target_name": "liquid helium", "weight": 3.0, "year": 2021}, {"source": "28", "target": "65", "source_name": "bcs theory", "target_name": "copper oxide", "weight": 7.0, "year": 2021}, {"source": "28", "target": "71", "source_name": "bcs theory", "target_name": "van hove", "weight": 2.0, "year": 2021}, {"source": "28", "target": "72", "source_name": "bcs theory", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "28", "target": "73", "source_name": "bcs theory", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "28", "target": "79", "source_name": "bcs theory", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "28", "target": "90", "source_name": "bcs theory", "target_name": "cooper pair", "weight": 4.0, "year": 2021}, {"source": "28", "target": "92", "source_name": "bcs theory", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "29", "target": "37", "source_name": "raman scattering", "target_name": "fermi surface", "weight": 1.0, "year": 2021}, {"source": "29", "target": "40", "source_name": "raman scattering", "target_name": "magnetic field", "weight": 1.0, "year": 2021}, {"source": "29", "target": "44", "source_name": "raman scattering", "target_name": "phase diagram", "weight": 2.0, "year": 2021}, {"source": "29", "target": "47", "source_name": "raman scattering", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2021}, {"source": "29", "target": "48", "source_name": "raman scattering", "target_name": "neutron scattering", "weight": 2.0, "year": 2021}, {"source": "29", "target": "55", "source_name": "raman scattering", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "29", "target": "56", "source_name": "raman scattering", "target_name": "hubbard model", "weight": 4.0, "year": 2021}, {"source": "29", "target": "70", "source_name": "raman scattering", "target_name": "meissner effect", "weight": 2.0, "year": 2021}, {"source": "29", "target": "87", "source_name": "raman scattering", "target_name": "charge transfer", "weight": 1.0, "year": 2021}, {"source": "30", "target": "31", "source_name": "fermi level", "target_name": "condensed matter", "weight": 2.0, "year": 2021}, {"source": "30", "target": "35", "source_name": "fermi level", "target_name": "space group", "weight": 1.0, "year": 2021}, {"source": "30", "target": "37", "source_name": "fermi level", "target_name": "fermi surface", "weight": 4.0, "year": 2021}, {"source": "30", "target": "44", "source_name": "fermi level", "target_name": "phase diagram", "weight": 3.0, "year": 2021}, {"source": "30", "target": "47", "source_name": "fermi level", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "30", "target": "49", "source_name": "fermi level", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "30", "target": "54", "source_name": "fermi level", "target_name": "coherence length", "weight": 2.0, "year": 2021}, {"source": "30", "target": "56", "source_name": "fermi level", "target_name": "hubbard model", "weight": 2.0, "year": 2021}, {"source": "30", "target": "58", "source_name": "fermi level", "target_name": "single crystal", "weight": 3.0, "year": 2021}, {"source": "30", "target": "60", "source_name": "fermi level", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "30", "target": "65", "source_name": "fermi level", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "30", "target": "71", "source_name": "fermi level", "target_name": "van hove", "weight": 3.0, "year": 2021}, {"source": "30", "target": "72", "source_name": "fermi level", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "30", "target": "73", "source_name": "fermi level", "target_name": "room temperature", "weight": 2.0, "year": 2021}, {"source": "30", "target": "79", "source_name": "fermi level", "target_name": "crystal structure", "weight": 3.0, "year": 2021}, {"source": "30", "target": "90", "source_name": "fermi level", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "30", "target": "91", "source_name": "fermi level", "target_name": "heat capacity", "weight": 4.0, "year": 2021}, {"source": "30", "target": "92", "source_name": "fermi level", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "31", "target": "37", "source_name": "condensed matter", "target_name": "fermi surface", "weight": 1.0, "year": 2021}, {"source": "31", "target": "40", "source_name": "condensed matter", "target_name": "magnetic field", "weight": 2.0, "year": 2021}, {"source": "31", "target": "44", "source_name": "condensed matter", "target_name": "phase diagram", "weight": 3.0, "year": 2021}, {"source": "31", "target": "48", "source_name": "condensed matter", "target_name": "neutron scattering", "weight": 4.0, "year": 2021}, {"source": "31", "target": "49", "source_name": "condensed matter", "target_name": "strongly correlated", "weight": 2.0, "year": 2021}, {"source": "31", "target": "53", "source_name": "condensed matter", "target_name": "spectral weight", "weight": 3.0, "year": 2021}, {"source": "31", "target": "55", "source_name": "condensed matter", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "31", "target": "58", "source_name": "condensed matter", "target_name": "single crystal", "weight": 5.0, "year": 2021}, {"source": "31", "target": "60", "source_name": "condensed matter", "target_name": "mott insulator", "weight": 2.0, "year": 2021}, {"source": "31", "target": "62", "source_name": "condensed matter", "target_name": "alternating current", "weight": 1.0, "year": 2021}, {"source": "31", "target": "64", "source_name": "condensed matter", "target_name": "liquid helium", "weight": 1.0, "year": 2021}, {"source": "31", "target": "65", "source_name": "condensed matter", "target_name": "copper oxide", "weight": 3.0, "year": 2021}, {"source": "31", "target": "68", "source_name": "condensed matter", "target_name": "nuclear magnetic resonance", "weight": 3.0, "year": 2021}, {"source": "31", "target": "73", "source_name": "condensed matter", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "31", "target": "78", "source_name": "condensed matter", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "31", "target": "79", "source_name": "condensed matter", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "31", "target": "84", "source_name": "condensed matter", "target_name": "ground state", "weight": 4.0, "year": 2021}, {"source": "31", "target": "87", "source_name": "condensed matter", "target_name": "charge transfer", "weight": 4.0, "year": 2021}, {"source": "31", "target": "90", "source_name": "condensed matter", "target_name": "cooper pair", "weight": 4.0, "year": 2021}, {"source": "31", "target": "91", "source_name": "condensed matter", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "32", "target": "40", "source_name": "flywheel energy storage", "target_name": "magnetic field", "weight": 2.0, "year": 2021}, {"source": "32", "target": "61", "source_name": "flywheel energy storage", "target_name": "synchronous motor", "weight": 1.0, "year": 2021}, {"source": "32", "target": "73", "source_name": "flywheel energy storage", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "32", "target": "77", "source_name": "flywheel energy storage", "target_name": "magnetic levitation", "weight": 2.0, "year": 2021}, {"source": "32", "target": "83", "source_name": "flywheel energy storage", "target_name": "permanent magnet", "weight": 4.0, "year": 2021}, {"source": "32", "target": "88", "source_name": "flywheel energy storage", "target_name": "energy storage", "weight": 10.0, "year": 2021}, {"source": "33", "target": "40", "source_name": "strontium titanate", "target_name": "magnetic field", "weight": 2.0, "year": 2021}, {"source": "33", "target": "58", "source_name": "strontium titanate", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "33", "target": "73", "source_name": "strontium titanate", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "34", "target": "37", "source_name": "exchange interaction", "target_name": "fermi surface", "weight": 4.0, "year": 2021}, {"source": "34", "target": "40", "source_name": "exchange interaction", "target_name": "magnetic field", "weight": 1.0, "year": 2021}, {"source": "34", "target": "44", "source_name": "exchange interaction", "target_name": "phase diagram", "weight": 2.0, "year": 2021}, {"source": "34", "target": "49", "source_name": "exchange interaction", "target_name": "strongly correlated", "weight": 4.0, "year": 2021}, {"source": "34", "target": "56", "source_name": "exchange interaction", "target_name": "hubbard model", "weight": 3.0, "year": 2021}, {"source": "34", "target": "57", "source_name": "exchange interaction", "target_name": "density functional theory", "weight": 1.0, "year": 2021}, {"source": "34", "target": "59", "source_name": "exchange interaction", "target_name": "monte carlo", "weight": 3.0, "year": 2021}, {"source": "34", "target": "66", "source_name": "exchange interaction", "target_name": "sulfur hydride", "weight": 2.0, "year": 2021}, {"source": "34", "target": "72", "source_name": "exchange interaction", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "34", "target": "79", "source_name": "exchange interaction", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "34", "target": "90", "source_name": "exchange interaction", "target_name": "cooper pair", "weight": 3.0, "year": 2021}, {"source": "35", "target": "40", "source_name": "space group", "target_name": "magnetic field", "weight": 2.0, "year": 2021}, {"source": "35", "target": "47", "source_name": "space group", "target_name": "magnetic susceptibility", "weight": 4.0, "year": 2021}, {"source": "35", "target": "73", "source_name": "space group", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "35", "target": "78", "source_name": "space group", "target_name": "charge carrier", "weight": 2.0, "year": 2021}, {"source": "35", "target": "79", "source_name": "space group", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "35", "target": "90", "source_name": "space group", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "35", "target": "91", "source_name": "space group", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "35", "target": "92", "source_name": "space group", "target_name": "ab initio", "weight": 2.0, "year": 2021}, {"source": "36", "target": "40", "source_name": "ion beam", "target_name": "magnetic field", "weight": 2.0, "year": 2021}, {"source": "36", "target": "41", "source_name": "ion beam", "target_name": "grain boundaries", "weight": 1.0, "year": 2021}, {"source": "36", "target": "50", "source_name": "ion beam", "target_name": "coated conductor", "weight": 2.0, "year": 2021}, {"source": "36", "target": "54", "source_name": "ion beam", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "36", "target": "63", "source_name": "ion beam", "target_name": "weak links", "weight": 2.0, "year": 2021}, {"source": "37", "target": "38", "source_name": "fermi surface", "target_name": "metallic hydrogen", "weight": 1.0, "year": 2021}, {"source": "37", "target": "40", "source_name": "fermi surface", "target_name": "magnetic field", "weight": 5.0, "year": 2021}, {"source": "37", "target": "44", "source_name": "fermi surface", "target_name": "phase diagram", "weight": 4.0, "year": 2021}, {"source": "37", "target": "46", "source_name": "fermi surface", "target_name": "iron pnictides", "weight": 3.0, "year": 2021}, {"source": "37", "target": "49", "source_name": "fermi surface", "target_name": "strongly correlated", "weight": 3.0, "year": 2021}, {"source": "37", "target": "53", "source_name": "fermi surface", "target_name": "spectral weight", "weight": 2.0, "year": 2021}, {"source": "37", "target": "54", "source_name": "fermi surface", "target_name": "coherence length", "weight": 4.0, "year": 2021}, {"source": "37", "target": "56", "source_name": "fermi surface", "target_name": "hubbard model", "weight": 4.0, "year": 2021}, {"source": "37", "target": "57", "source_name": "fermi surface", "target_name": "density functional theory", "weight": 2.0, "year": 2021}, {"source": "37", "target": "58", "source_name": "fermi surface", "target_name": "single crystal", "weight": 4.0, "year": 2021}, {"source": "37", "target": "60", "source_name": "fermi surface", "target_name": "mott insulator", "weight": 2.0, "year": 2021}, {"source": "37", "target": "65", "source_name": "fermi surface", "target_name": "copper oxide", "weight": 3.0, "year": 2021}, {"source": "37", "target": "68", "source_name": "fermi surface", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2021}, {"source": "37", "target": "78", "source_name": "fermi surface", "target_name": "charge carrier", "weight": 5.0, "year": 2021}, {"source": "37", "target": "79", "source_name": "fermi surface", "target_name": "crystal structure", "weight": 8.0, "year": 2021}, {"source": "37", "target": "84", "source_name": "fermi surface", "target_name": "ground state", "weight": 2.0, "year": 2021}, {"source": "37", "target": "85", "source_name": "fermi surface", "target_name": "perturbation theory", "weight": 5.0, "year": 2021}, {"source": "37", "target": "87", "source_name": "fermi surface", "target_name": "charge transfer", "weight": 1.0, "year": 2021}, {"source": "37", "target": "90", "source_name": "fermi surface", "target_name": "cooper pair", "weight": 11.0, "year": 2021}, {"source": "37", "target": "91", "source_name": "fermi surface", "target_name": "heat capacity", "weight": 3.0, "year": 2021}, {"source": "37", "target": "92", "source_name": "fermi surface", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "38", "target": "40", "source_name": "metallic hydrogen", "target_name": "magnetic field", "weight": 1.0, "year": 2021}, {"source": "38", "target": "42", "source_name": "metallic hydrogen", "target_name": "rare earth", "weight": 1.0, "year": 2021}, {"source": "38", "target": "66", "source_name": "metallic hydrogen", "target_name": "sulfur hydride", "weight": 1.0, "year": 2021}, {"source": "38", "target": "73", "source_name": "metallic hydrogen", "target_name": "room temperature", "weight": 2.0, "year": 2021}, {"source": "38", "target": "79", "source_name": "metallic hydrogen", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "38", "target": "87", "source_name": "metallic hydrogen", "target_name": "charge transfer", "weight": 1.0, "year": 2021}, {"source": "38", "target": "92", "source_name": "metallic hydrogen", "target_name": "ab initio", "weight": 3.0, "year": 2021}, {"source": "39", "target": "40", "source_name": "finite element method", "target_name": "magnetic field", "weight": 11.0, "year": 2021}, {"source": "39", "target": "42", "source_name": "finite element method", "target_name": "rare earth", "weight": 1.0, "year": 2021}, {"source": "39", "target": "50", "source_name": "finite element method", "target_name": "coated conductor", "weight": 1.0, "year": 2021}, {"source": "39", "target": "51", "source_name": "finite element method", "target_name": "wind turbine", "weight": 2.0, "year": 2021}, {"source": "39", "target": "61", "source_name": "finite element method", "target_name": "synchronous motor", "weight": 2.0, "year": 2021}, {"source": "39", "target": "65", "source_name": "finite element method", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "39", "target": "68", "source_name": "finite element method", "target_name": "nuclear magnetic resonance", "weight": 1.0, "year": 2021}, {"source": "39", "target": "80", "source_name": "finite element method", "target_name": "quench propagation", "weight": 2.0, "year": 2021}, {"source": "39", "target": "81", "source_name": "finite element method", "target_name": "finite element", "weight": 16.0, "year": 2021}, {"source": "39", "target": "83", "source_name": "finite element method", "target_name": "permanent magnet", "weight": 3.0, "year": 2021}, {"source": "39", "target": "86", "source_name": "finite element method", "target_name": "induction motor", "weight": 2.0, "year": 2021}, {"source": "39", "target": "88", "source_name": "finite element method", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "40", "target": "41", "source_name": "magnetic field", "target_name": "grain boundaries", "weight": 5.0, "year": 2021}, {"source": "40", "target": "42", "source_name": "magnetic field", "target_name": "rare earth", "weight": 7.0, "year": 2021}, {"source": "40", "target": "44", "source_name": "magnetic field", "target_name": "phase diagram", "weight": 15.0, "year": 2021}, {"source": "40", "target": "46", "source_name": "magnetic field", "target_name": "iron pnictides", "weight": 1.0, "year": 2021}, {"source": "40", "target": "47", "source_name": "magnetic field", "target_name": "magnetic susceptibility", "weight": 12.0, "year": 2021}, {"source": "40", "target": "48", "source_name": "magnetic field", "target_name": "neutron scattering", "weight": 2.0, "year": 2021}, {"source": "40", "target": "49", "source_name": "magnetic field", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "40", "target": "50", "source_name": "magnetic field", "target_name": "coated conductor", "weight": 15.0, "year": 2021}, {"source": "40", "target": "51", "source_name": "magnetic field", "target_name": "wind turbine", "weight": 4.0, "year": 2021}, {"source": "40", "target": "52", "source_name": "magnetic field", "target_name": "hydrogen sulfide", "weight": 2.0, "year": 2021}, {"source": "40", "target": "54", "source_name": "magnetic field", "target_name": "coherence length", "weight": 11.0, "year": 2021}, {"source": "40", "target": "55", "source_name": "magnetic field", "target_name": "optimally doped", "weight": 3.0, "year": 2021}, {"source": "40", "target": "57", "source_name": "magnetic field", "target_name": "density functional theory", "weight": 5.0, "year": 2021}, {"source": "40", "target": "58", "source_name": "magnetic field", "target_name": "single crystal", "weight": 28.0, "year": 2021}, {"source": "40", "target": "61", "source_name": "magnetic field", "target_name": "synchronous motor", "weight": 10.0, "year": 2021}, {"source": "40", "target": "62", "source_name": "magnetic field", "target_name": "alternating current", "weight": 3.0, "year": 2021}, {"source": "40", "target": "63", "source_name": "magnetic field", "target_name": "weak links", "weight": 4.0, "year": 2021}, {"source": "40", "target": "64", "source_name": "magnetic field", "target_name": "liquid helium", "weight": 17.0, "year": 2021}, {"source": "40", "target": "65", "source_name": "magnetic field", "target_name": "copper oxide", "weight": 14.0, "year": 2021}, {"source": "40", "target": "66", "source_name": "magnetic field", "target_name": "sulfur hydride", "weight": 3.0, "year": 2021}, {"source": "40", "target": "67", "source_name": "magnetic field", "target_name": "magnesium diboride", "weight": 2.0, "year": 2021}, {"source": "40", "target": "68", "source_name": "magnetic field", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2021}, {"source": "40", "target": "72", "source_name": "magnetic field", "target_name": "electrical resistance", "weight": 7.0, "year": 2021}, {"source": "40", "target": "73", "source_name": "magnetic field", "target_name": "room temperature", "weight": 22.0, "year": 2021}, {"source": "40", "target": "74", "source_name": "magnetic field", "target_name": "transmission line", "weight": 1.0, "year": 2021}, {"source": "40", "target": "75", "source_name": "magnetic field", "target_name": "stainless steel", "weight": 1.0, "year": 2021}, {"source": "40", "target": "77", "source_name": "magnetic field", "target_name": "magnetic levitation", "weight": 10.0, "year": 2021}, {"source": "40", "target": "78", "source_name": "magnetic field", "target_name": "charge carrier", "weight": 4.0, "year": 2021}, {"source": "40", "target": "79", "source_name": "magnetic field", "target_name": "crystal structure", "weight": 3.0, "year": 2021}, {"source": "40", "target": "80", "source_name": "magnetic field", "target_name": "quench propagation", "weight": 4.0, "year": 2021}, {"source": "40", "target": "81", "source_name": "magnetic field", "target_name": "finite element", "weight": 12.0, "year": 2021}, {"source": "40", "target": "83", "source_name": "magnetic field", "target_name": "permanent magnet", "weight": 12.0, "year": 2021}, {"source": "40", "target": "84", "source_name": "magnetic field", "target_name": "ground state", "weight": 10.0, "year": 2021}, {"source": "40", "target": "86", "source_name": "magnetic field", "target_name": "induction motor", "weight": 1.0, "year": 2021}, {"source": "40", "target": "87", "source_name": "magnetic field", "target_name": "charge transfer", "weight": 1.0, "year": 2021}, {"source": "40", "target": "88", "source_name": "magnetic field", "target_name": "energy storage", "weight": 13.0, "year": 2021}, {"source": "40", "target": "90", "source_name": "magnetic field", "target_name": "cooper pair", "weight": 8.0, "year": 2021}, {"source": "41", "target": "42", "source_name": "grain boundaries", "target_name": "rare earth", "weight": 1.0, "year": 2021}, {"source": "41", "target": "46", "source_name": "grain boundaries", "target_name": "iron pnictides", "weight": 1.0, "year": 2021}, {"source": "41", "target": "50", "source_name": "grain boundaries", "target_name": "coated conductor", "weight": 1.0, "year": 2021}, {"source": "41", "target": "54", "source_name": "grain boundaries", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "41", "target": "58", "source_name": "grain boundaries", "target_name": "single crystal", "weight": 2.0, "year": 2021}, {"source": "41", "target": "63", "source_name": "grain boundaries", "target_name": "weak links", "weight": 1.0, "year": 2021}, {"source": "41", "target": "65", "source_name": "grain boundaries", "target_name": "copper oxide", "weight": 2.0, "year": 2021}, {"source": "41", "target": "79", "source_name": "grain boundaries", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "41", "target": "90", "source_name": "grain boundaries", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "42", "target": "44", "source_name": "rare earth", "target_name": "phase diagram", "weight": 3.0, "year": 2021}, {"source": "42", "target": "48", "source_name": "rare earth", "target_name": "neutron scattering", "weight": 1.0, "year": 2021}, {"source": "42", "target": "50", "source_name": "rare earth", "target_name": "coated conductor", "weight": 1.0, "year": 2021}, {"source": "42", "target": "65", "source_name": "rare earth", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "42", "target": "66", "source_name": "rare earth", "target_name": "sulfur hydride", "weight": 1.0, "year": 2021}, {"source": "42", "target": "68", "source_name": "rare earth", "target_name": "nuclear magnetic resonance", "weight": 2.0, "year": 2021}, {"source": "42", "target": "73", "source_name": "rare earth", "target_name": "room temperature", "weight": 2.0, "year": 2021}, {"source": "42", "target": "78", "source_name": "rare earth", "target_name": "charge carrier", "weight": 2.0, "year": 2021}, {"source": "42", "target": "79", "source_name": "rare earth", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "42", "target": "81", "source_name": "rare earth", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "42", "target": "83", "source_name": "rare earth", "target_name": "permanent magnet", "weight": 1.0, "year": 2021}, {"source": "42", "target": "84", "source_name": "rare earth", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "42", "target": "92", "source_name": "rare earth", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "43", "target": "68", "source_name": "transmission electron microscopy", "target_name": "nuclear magnetic resonance", "weight": 5.0, "year": 2021}, {"source": "43", "target": "75", "source_name": "transmission electron microscopy", "target_name": "stainless steel", "weight": 1.0, "year": 2021}, {"source": "44", "target": "46", "source_name": "phase diagram", "target_name": "iron pnictides", "weight": 6.0, "year": 2021}, {"source": "44", "target": "47", "source_name": "phase diagram", "target_name": "magnetic susceptibility", "weight": 6.0, "year": 2021}, {"source": "44", "target": "48", "source_name": "phase diagram", "target_name": "neutron scattering", "weight": 6.0, "year": 2021}, {"source": "44", "target": "49", "source_name": "phase diagram", "target_name": "strongly correlated", "weight": 6.0, "year": 2021}, {"source": "44", "target": "50", "source_name": "phase diagram", "target_name": "coated conductor", "weight": 1.0, "year": 2021}, {"source": "44", "target": "53", "source_name": "phase diagram", "target_name": "spectral weight", "weight": 1.0, "year": 2021}, {"source": "44", "target": "54", "source_name": "phase diagram", "target_name": "coherence length", "weight": 2.0, "year": 2021}, {"source": "44", "target": "55", "source_name": "phase diagram", "target_name": "optimally doped", "weight": 3.0, "year": 2021}, {"source": "44", "target": "56", "source_name": "phase diagram", "target_name": "hubbard model", "weight": 6.0, "year": 2021}, {"source": "44", "target": "57", "source_name": "phase diagram", "target_name": "density functional theory", "weight": 2.0, "year": 2021}, {"source": "44", "target": "58", "source_name": "phase diagram", "target_name": "single crystal", "weight": 13.0, "year": 2021}, {"source": "44", "target": "59", "source_name": "phase diagram", "target_name": "monte carlo", "weight": 3.0, "year": 2021}, {"source": "44", "target": "60", "source_name": "phase diagram", "target_name": "mott insulator", "weight": 4.0, "year": 2021}, {"source": "44", "target": "63", "source_name": "phase diagram", "target_name": "weak links", "weight": 2.0, "year": 2021}, {"source": "44", "target": "65", "source_name": "phase diagram", "target_name": "copper oxide", "weight": 11.0, "year": 2021}, {"source": "44", "target": "66", "source_name": "phase diagram", "target_name": "sulfur hydride", "weight": 4.0, "year": 2021}, {"source": "44", "target": "67", "source_name": "phase diagram", "target_name": "magnesium diboride", "weight": 2.0, "year": 2021}, {"source": "44", "target": "69", "source_name": "phase diagram", "target_name": "selenium hydrides", "weight": 5.0, "year": 2021}, {"source": "44", "target": "70", "source_name": "phase diagram", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "44", "target": "71", "source_name": "phase diagram", "target_name": "van hove", "weight": 1.0, "year": 2021}, {"source": "44", "target": "73", "source_name": "phase diagram", "target_name": "room temperature", "weight": 7.0, "year": 2021}, {"source": "44", "target": "74", "source_name": "phase diagram", "target_name": "transmission line", "weight": 1.0, "year": 2021}, {"source": "44", "target": "78", "source_name": "phase diagram", "target_name": "charge carrier", "weight": 4.0, "year": 2021}, {"source": "44", "target": "79", "source_name": "phase diagram", "target_name": "crystal structure", "weight": 4.0, "year": 2021}, {"source": "44", "target": "83", "source_name": "phase diagram", "target_name": "permanent magnet", "weight": 1.0, "year": 2021}, {"source": "44", "target": "84", "source_name": "phase diagram", "target_name": "ground state", "weight": 8.0, "year": 2021}, {"source": "44", "target": "85", "source_name": "phase diagram", "target_name": "perturbation theory", "weight": 1.0, "year": 2021}, {"source": "44", "target": "88", "source_name": "phase diagram", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "44", "target": "90", "source_name": "phase diagram", "target_name": "cooper pair", "weight": 3.0, "year": 2021}, {"source": "44", "target": "91", "source_name": "phase diagram", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "44", "target": "92", "source_name": "phase diagram", "target_name": "ab initio", "weight": 2.0, "year": 2021}, {"source": "45", "target": "54", "source_name": "power transmission", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "45", "target": "70", "source_name": "power transmission", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "45", "target": "74", "source_name": "power transmission", "target_name": "transmission line", "weight": 1.0, "year": 2021}, {"source": "45", "target": "88", "source_name": "power transmission", "target_name": "energy storage", "weight": 3.0, "year": 2021}, {"source": "45", "target": "90", "source_name": "power transmission", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "46", "target": "47", "source_name": "iron pnictides", "target_name": "magnetic susceptibility", "weight": 1.0, "year": 2021}, {"source": "46", "target": "48", "source_name": "iron pnictides", "target_name": "neutron scattering", "weight": 3.0, "year": 2021}, {"source": "46", "target": "49", "source_name": "iron pnictides", "target_name": "strongly correlated", "weight": 2.0, "year": 2021}, {"source": "46", "target": "53", "source_name": "iron pnictides", "target_name": "spectral weight", "weight": 1.0, "year": 2021}, {"source": "46", "target": "54", "source_name": "iron pnictides", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "46", "target": "55", "source_name": "iron pnictides", "target_name": "optimally doped", "weight": 2.0, "year": 2021}, {"source": "46", "target": "56", "source_name": "iron pnictides", "target_name": "hubbard model", "weight": 3.0, "year": 2021}, {"source": "46", "target": "58", "source_name": "iron pnictides", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "46", "target": "65", "source_name": "iron pnictides", "target_name": "copper oxide", "weight": 7.0, "year": 2021}, {"source": "46", "target": "67", "source_name": "iron pnictides", "target_name": "magnesium diboride", "weight": 2.0, "year": 2021}, {"source": "46", "target": "73", "source_name": "iron pnictides", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "46", "target": "84", "source_name": "iron pnictides", "target_name": "ground state", "weight": 2.0, "year": 2021}, {"source": "46", "target": "85", "source_name": "iron pnictides", "target_name": "perturbation theory", "weight": 3.0, "year": 2021}, {"source": "46", "target": "90", "source_name": "iron pnictides", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "47", "target": "49", "source_name": "magnetic susceptibility", "target_name": "strongly correlated", "weight": 1.0, "year": 2021}, {"source": "47", "target": "52", "source_name": "magnetic susceptibility", "target_name": "hydrogen sulfide", "weight": 1.0, "year": 2021}, {"source": "47", "target": "55", "source_name": "magnetic susceptibility", "target_name": "optimally doped", "weight": 2.0, "year": 2021}, {"source": "47", "target": "58", "source_name": "magnetic susceptibility", "target_name": "single crystal", "weight": 6.0, "year": 2021}, {"source": "47", "target": "64", "source_name": "magnetic susceptibility", "target_name": "liquid helium", "weight": 1.0, "year": 2021}, {"source": "47", "target": "65", "source_name": "magnetic susceptibility", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "47", "target": "66", "source_name": "magnetic susceptibility", "target_name": "sulfur hydride", "weight": 5.0, "year": 2021}, {"source": "47", "target": "70", "source_name": "magnetic susceptibility", "target_name": "meissner effect", "weight": 5.0, "year": 2021}, {"source": "47", "target": "72", "source_name": "magnetic susceptibility", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "47", "target": "73", "source_name": "magnetic susceptibility", "target_name": "room temperature", "weight": 4.0, "year": 2021}, {"source": "47", "target": "78", "source_name": "magnetic susceptibility", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "47", "target": "79", "source_name": "magnetic susceptibility", "target_name": "crystal structure", "weight": 6.0, "year": 2021}, {"source": "47", "target": "84", "source_name": "magnetic susceptibility", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "47", "target": "87", "source_name": "magnetic susceptibility", "target_name": "charge transfer", "weight": 1.0, "year": 2021}, {"source": "47", "target": "90", "source_name": "magnetic susceptibility", "target_name": "cooper pair", "weight": 2.0, "year": 2021}, {"source": "47", "target": "91", "source_name": "magnetic susceptibility", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "48", "target": "53", "source_name": "neutron scattering", "target_name": "spectral weight", "weight": 6.0, "year": 2021}, {"source": "48", "target": "56", "source_name": "neutron scattering", "target_name": "hubbard model", "weight": 2.0, "year": 2021}, {"source": "48", "target": "58", "source_name": "neutron scattering", "target_name": "single crystal", "weight": 2.0, "year": 2021}, {"source": "48", "target": "64", "source_name": "neutron scattering", "target_name": "liquid helium", "weight": 1.0, "year": 2021}, {"source": "48", "target": "65", "source_name": "neutron scattering", "target_name": "copper oxide", "weight": 6.0, "year": 2021}, {"source": "48", "target": "70", "source_name": "neutron scattering", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "48", "target": "73", "source_name": "neutron scattering", "target_name": "room temperature", "weight": 2.0, "year": 2021}, {"source": "48", "target": "79", "source_name": "neutron scattering", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "48", "target": "84", "source_name": "neutron scattering", "target_name": "ground state", "weight": 6.0, "year": 2021}, {"source": "48", "target": "90", "source_name": "neutron scattering", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "49", "target": "53", "source_name": "strongly correlated", "target_name": "spectral weight", "weight": 1.0, "year": 2021}, {"source": "49", "target": "55", "source_name": "strongly correlated", "target_name": "optimally doped", "weight": 4.0, "year": 2021}, {"source": "49", "target": "56", "source_name": "strongly correlated", "target_name": "hubbard model", "weight": 11.0, "year": 2021}, {"source": "49", "target": "58", "source_name": "strongly correlated", "target_name": "single crystal", "weight": 3.0, "year": 2021}, {"source": "49", "target": "59", "source_name": "strongly correlated", "target_name": "monte carlo", "weight": 12.0, "year": 2021}, {"source": "49", "target": "60", "source_name": "strongly correlated", "target_name": "mott insulator", "weight": 2.0, "year": 2021}, {"source": "49", "target": "65", "source_name": "strongly correlated", "target_name": "copper oxide", "weight": 3.0, "year": 2021}, {"source": "49", "target": "67", "source_name": "strongly correlated", "target_name": "magnesium diboride", "weight": 1.0, "year": 2021}, {"source": "49", "target": "73", "source_name": "strongly correlated", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "49", "target": "78", "source_name": "strongly correlated", "target_name": "charge carrier", "weight": 2.0, "year": 2021}, {"source": "49", "target": "84", "source_name": "strongly correlated", "target_name": "ground state", "weight": 7.0, "year": 2021}, {"source": "49", "target": "85", "source_name": "strongly correlated", "target_name": "perturbation theory", "weight": 1.0, "year": 2021}, {"source": "50", "target": "58", "source_name": "coated conductor", "target_name": "single crystal", "weight": 2.0, "year": 2021}, {"source": "50", "target": "61", "source_name": "coated conductor", "target_name": "synchronous motor", "weight": 1.0, "year": 2021}, {"source": "50", "target": "63", "source_name": "coated conductor", "target_name": "weak links", "weight": 1.0, "year": 2021}, {"source": "50", "target": "64", "source_name": "coated conductor", "target_name": "liquid helium", "weight": 3.0, "year": 2021}, {"source": "50", "target": "65", "source_name": "coated conductor", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "50", "target": "67", "source_name": "coated conductor", "target_name": "magnesium diboride", "weight": 1.0, "year": 2021}, {"source": "50", "target": "68", "source_name": "coated conductor", "target_name": "nuclear magnetic resonance", "weight": 3.0, "year": 2021}, {"source": "50", "target": "72", "source_name": "coated conductor", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "50", "target": "73", "source_name": "coated conductor", "target_name": "room temperature", "weight": 2.0, "year": 2021}, {"source": "50", "target": "81", "source_name": "coated conductor", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "50", "target": "83", "source_name": "coated conductor", "target_name": "permanent magnet", "weight": 2.0, "year": 2021}, {"source": "50", "target": "88", "source_name": "coated conductor", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "50", "target": "89", "source_name": "coated conductor", "target_name": "sol gel", "weight": 1.0, "year": 2021}, {"source": "50", "target": "91", "source_name": "coated conductor", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "51", "target": "81", "source_name": "wind turbine", "target_name": "finite element", "weight": 4.0, "year": 2021}, {"source": "51", "target": "86", "source_name": "wind turbine", "target_name": "induction motor", "weight": 1.0, "year": 2021}, {"source": "52", "target": "57", "source_name": "hydrogen sulfide", "target_name": "density functional theory", "weight": 1.0, "year": 2021}, {"source": "52", "target": "66", "source_name": "hydrogen sulfide", "target_name": "sulfur hydride", "weight": 2.0, "year": 2021}, {"source": "52", "target": "73", "source_name": "hydrogen sulfide", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "52", "target": "79", "source_name": "hydrogen sulfide", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "52", "target": "92", "source_name": "hydrogen sulfide", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "53", "target": "54", "source_name": "spectral weight", "target_name": "coherence length", "weight": 1.0, "year": 2021}, {"source": "53", "target": "55", "source_name": "spectral weight", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "53", "target": "58", "source_name": "spectral weight", "target_name": "single crystal", "weight": 3.0, "year": 2021}, {"source": "53", "target": "60", "source_name": "spectral weight", "target_name": "mott insulator", "weight": 3.0, "year": 2021}, {"source": "53", "target": "78", "source_name": "spectral weight", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "53", "target": "84", "source_name": "spectral weight", "target_name": "ground state", "weight": 4.0, "year": 2021}, {"source": "53", "target": "87", "source_name": "spectral weight", "target_name": "charge transfer", "weight": 2.0, "year": 2021}, {"source": "54", "target": "55", "source_name": "coherence length", "target_name": "optimally doped", "weight": 1.0, "year": 2021}, {"source": "54", "target": "58", "source_name": "coherence length", "target_name": "single crystal", "weight": 9.0, "year": 2021}, {"source": "54", "target": "60", "source_name": "coherence length", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "54", "target": "65", "source_name": "coherence length", "target_name": "copper oxide", "weight": 3.0, "year": 2021}, {"source": "54", "target": "67", "source_name": "coherence length", "target_name": "magnesium diboride", "weight": 1.0, "year": 2021}, {"source": "54", "target": "70", "source_name": "coherence length", "target_name": "meissner effect", "weight": 2.0, "year": 2021}, {"source": "54", "target": "71", "source_name": "coherence length", "target_name": "van hove", "weight": 1.0, "year": 2021}, {"source": "54", "target": "73", "source_name": "coherence length", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "54", "target": "77", "source_name": "coherence length", "target_name": "magnetic levitation", "weight": 1.0, "year": 2021}, {"source": "54", "target": "79", "source_name": "coherence length", "target_name": "crystal structure", "weight": 3.0, "year": 2021}, {"source": "54", "target": "84", "source_name": "coherence length", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "54", "target": "88", "source_name": "coherence length", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "54", "target": "90", "source_name": "coherence length", "target_name": "cooper pair", "weight": 6.0, "year": 2021}, {"source": "54", "target": "91", "source_name": "coherence length", "target_name": "heat capacity", "weight": 2.0, "year": 2021}, {"source": "55", "target": "58", "source_name": "optimally doped", "target_name": "single crystal", "weight": 2.0, "year": 2021}, {"source": "55", "target": "60", "source_name": "optimally doped", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "55", "target": "65", "source_name": "optimally doped", "target_name": "copper oxide", "weight": 3.0, "year": 2021}, {"source": "55", "target": "79", "source_name": "optimally doped", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "55", "target": "84", "source_name": "optimally doped", "target_name": "ground state", "weight": 3.0, "year": 2021}, {"source": "55", "target": "85", "source_name": "optimally doped", "target_name": "perturbation theory", "weight": 1.0, "year": 2021}, {"source": "56", "target": "58", "source_name": "hubbard model", "target_name": "single crystal", "weight": 1.0, "year": 2021}, {"source": "56", "target": "59", "source_name": "hubbard model", "target_name": "monte carlo", "weight": 11.0, "year": 2021}, {"source": "56", "target": "60", "source_name": "hubbard model", "target_name": "mott insulator", "weight": 1.0, "year": 2021}, {"source": "56", "target": "65", "source_name": "hubbard model", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "56", "target": "84", "source_name": "hubbard model", "target_name": "ground state", "weight": 4.0, "year": 2021}, {"source": "56", "target": "85", "source_name": "hubbard model", "target_name": "perturbation theory", "weight": 4.0, "year": 2021}, {"source": "56", "target": "90", "source_name": "hubbard model", "target_name": "cooper pair", "weight": 3.0, "year": 2021}, {"source": "57", "target": "69", "source_name": "density functional theory", "target_name": "selenium hydrides", "weight": 2.0, "year": 2021}, {"source": "57", "target": "73", "source_name": "density functional theory", "target_name": "room temperature", "weight": 4.0, "year": 2021}, {"source": "57", "target": "79", "source_name": "density functional theory", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "57", "target": "90", "source_name": "density functional theory", "target_name": "cooper pair", "weight": 2.0, "year": 2021}, {"source": "57", "target": "92", "source_name": "density functional theory", "target_name": "ab initio", "weight": 3.0, "year": 2021}, {"source": "58", "target": "62", "source_name": "single crystal", "target_name": "alternating current", "weight": 1.0, "year": 2021}, {"source": "58", "target": "65", "source_name": "single crystal", "target_name": "copper oxide", "weight": 4.0, "year": 2021}, {"source": "58", "target": "67", "source_name": "single crystal", "target_name": "magnesium diboride", "weight": 3.0, "year": 2021}, {"source": "58", "target": "68", "source_name": "single crystal", "target_name": "nuclear magnetic resonance", "weight": 3.0, "year": 2021}, {"source": "58", "target": "70", "source_name": "single crystal", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "58", "target": "72", "source_name": "single crystal", "target_name": "electrical resistance", "weight": 4.0, "year": 2021}, {"source": "58", "target": "73", "source_name": "single crystal", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "58", "target": "78", "source_name": "single crystal", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "58", "target": "79", "source_name": "single crystal", "target_name": "crystal structure", "weight": 5.0, "year": 2021}, {"source": "58", "target": "83", "source_name": "single crystal", "target_name": "permanent magnet", "weight": 1.0, "year": 2021}, {"source": "58", "target": "84", "source_name": "single crystal", "target_name": "ground state", "weight": 3.0, "year": 2021}, {"source": "58", "target": "90", "source_name": "single crystal", "target_name": "cooper pair", "weight": 6.0, "year": 2021}, {"source": "58", "target": "91", "source_name": "single crystal", "target_name": "heat capacity", "weight": 4.0, "year": 2021}, {"source": "59", "target": "73", "source_name": "monte carlo", "target_name": "room temperature", "weight": 2.0, "year": 2021}, {"source": "59", "target": "84", "source_name": "monte carlo", "target_name": "ground state", "weight": 8.0, "year": 2021}, {"source": "60", "target": "65", "source_name": "mott insulator", "target_name": "copper oxide", "weight": 2.0, "year": 2021}, {"source": "60", "target": "71", "source_name": "mott insulator", "target_name": "van hove", "weight": 1.0, "year": 2021}, {"source": "60", "target": "78", "source_name": "mott insulator", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "60", "target": "79", "source_name": "mott insulator", "target_name": "crystal structure", "weight": 1.0, "year": 2021}, {"source": "60", "target": "84", "source_name": "mott insulator", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "60", "target": "87", "source_name": "mott insulator", "target_name": "charge transfer", "weight": 2.0, "year": 2021}, {"source": "60", "target": "90", "source_name": "mott insulator", "target_name": "cooper pair", "weight": 2.0, "year": 2021}, {"source": "61", "target": "64", "source_name": "synchronous motor", "target_name": "liquid helium", "weight": 1.0, "year": 2021}, {"source": "61", "target": "81", "source_name": "synchronous motor", "target_name": "finite element", "weight": 2.0, "year": 2021}, {"source": "61", "target": "83", "source_name": "synchronous motor", "target_name": "permanent magnet", "weight": 3.0, "year": 2021}, {"source": "61", "target": "88", "source_name": "synchronous motor", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "62", "target": "65", "source_name": "alternating current", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "62", "target": "77", "source_name": "alternating current", "target_name": "magnetic levitation", "weight": 1.0, "year": 2021}, {"source": "62", "target": "81", "source_name": "alternating current", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "62", "target": "83", "source_name": "alternating current", "target_name": "permanent magnet", "weight": 1.0, "year": 2021}, {"source": "62", "target": "91", "source_name": "alternating current", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "63", "target": "72", "source_name": "weak links", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "63", "target": "74", "source_name": "weak links", "target_name": "transmission line", "weight": 1.0, "year": 2021}, {"source": "63", "target": "88", "source_name": "weak links", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "64", "target": "65", "source_name": "liquid helium", "target_name": "copper oxide", "weight": 1.0, "year": 2021}, {"source": "64", "target": "73", "source_name": "liquid helium", "target_name": "room temperature", "weight": 5.0, "year": 2021}, {"source": "64", "target": "74", "source_name": "liquid helium", "target_name": "transmission line", "weight": 1.0, "year": 2021}, {"source": "64", "target": "75", "source_name": "liquid helium", "target_name": "stainless steel", "weight": 2.0, "year": 2021}, {"source": "64", "target": "76", "source_name": "liquid helium", "target_name": "heat exchanger", "weight": 1.0, "year": 2021}, {"source": "64", "target": "77", "source_name": "liquid helium", "target_name": "magnetic levitation", "weight": 1.0, "year": 2021}, {"source": "64", "target": "80", "source_name": "liquid helium", "target_name": "quench propagation", "weight": 1.0, "year": 2021}, {"source": "64", "target": "81", "source_name": "liquid helium", "target_name": "finite element", "weight": 2.0, "year": 2021}, {"source": "64", "target": "83", "source_name": "liquid helium", "target_name": "permanent magnet", "weight": 2.0, "year": 2021}, {"source": "64", "target": "88", "source_name": "liquid helium", "target_name": "energy storage", "weight": 2.0, "year": 2021}, {"source": "65", "target": "67", "source_name": "copper oxide", "target_name": "magnesium diboride", "weight": 3.0, "year": 2021}, {"source": "65", "target": "71", "source_name": "copper oxide", "target_name": "van hove", "weight": 1.0, "year": 2021}, {"source": "65", "target": "73", "source_name": "copper oxide", "target_name": "room temperature", "weight": 4.0, "year": 2021}, {"source": "65", "target": "79", "source_name": "copper oxide", "target_name": "crystal structure", "weight": 5.0, "year": 2021}, {"source": "65", "target": "81", "source_name": "copper oxide", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "65", "target": "83", "source_name": "copper oxide", "target_name": "permanent magnet", "weight": 1.0, "year": 2021}, {"source": "65", "target": "84", "source_name": "copper oxide", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "65", "target": "87", "source_name": "copper oxide", "target_name": "charge transfer", "weight": 1.0, "year": 2021}, {"source": "65", "target": "90", "source_name": "copper oxide", "target_name": "cooper pair", "weight": 5.0, "year": 2021}, {"source": "65", "target": "91", "source_name": "copper oxide", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "66", "target": "69", "source_name": "sulfur hydride", "target_name": "selenium hydrides", "weight": 4.0, "year": 2021}, {"source": "66", "target": "70", "source_name": "sulfur hydride", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "66", "target": "72", "source_name": "sulfur hydride", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "66", "target": "73", "source_name": "sulfur hydride", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "66", "target": "79", "source_name": "sulfur hydride", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "67", "target": "70", "source_name": "magnesium diboride", "target_name": "meissner effect", "weight": 1.0, "year": 2021}, {"source": "67", "target": "72", "source_name": "magnesium diboride", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "67", "target": "83", "source_name": "magnesium diboride", "target_name": "permanent magnet", "weight": 1.0, "year": 2021}, {"source": "67", "target": "88", "source_name": "magnesium diboride", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "68", "target": "72", "source_name": "nuclear magnetic resonance", "target_name": "electrical resistance", "weight": 1.0, "year": 2021}, {"source": "68", "target": "77", "source_name": "nuclear magnetic resonance", "target_name": "magnetic levitation", "weight": 1.0, "year": 2021}, {"source": "68", "target": "79", "source_name": "nuclear magnetic resonance", "target_name": "crystal structure", "weight": 3.0, "year": 2021}, {"source": "68", "target": "81", "source_name": "nuclear magnetic resonance", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "68", "target": "88", "source_name": "nuclear magnetic resonance", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "70", "target": "73", "source_name": "meissner effect", "target_name": "room temperature", "weight": 3.0, "year": 2021}, {"source": "70", "target": "79", "source_name": "meissner effect", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "70", "target": "81", "source_name": "meissner effect", "target_name": "finite element", "weight": 1.0, "year": 2021}, {"source": "70", "target": "87", "source_name": "meissner effect", "target_name": "charge transfer", "weight": 1.0, "year": 2021}, {"source": "70", "target": "88", "source_name": "meissner effect", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "70", "target": "90", "source_name": "meissner effect", "target_name": "cooper pair", "weight": 3.0, "year": 2021}, {"source": "70", "target": "91", "source_name": "meissner effect", "target_name": "heat capacity", "weight": 1.0, "year": 2021}, {"source": "71", "target": "73", "source_name": "van hove", "target_name": "room temperature", "weight": 1.0, "year": 2021}, {"source": "72", "target": "73", "source_name": "electrical resistance", "target_name": "room temperature", "weight": 6.0, "year": 2021}, {"source": "72", "target": "77", "source_name": "electrical resistance", "target_name": "magnetic levitation", "weight": 3.0, "year": 2021}, {"source": "72", "target": "78", "source_name": "electrical resistance", "target_name": "charge carrier", "weight": 1.0, "year": 2021}, {"source": "72", "target": "79", "source_name": "electrical resistance", "target_name": "crystal structure", "weight": 3.0, "year": 2021}, {"source": "72", "target": "88", "source_name": "electrical resistance", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "73", "target": "75", "source_name": "room temperature", "target_name": "stainless steel", "weight": 1.0, "year": 2021}, {"source": "73", "target": "77", "source_name": "room temperature", "target_name": "magnetic levitation", "weight": 1.0, "year": 2021}, {"source": "73", "target": "78", "source_name": "room temperature", "target_name": "charge carrier", "weight": 3.0, "year": 2021}, {"source": "73", "target": "79", "source_name": "room temperature", "target_name": "crystal structure", "weight": 3.0, "year": 2021}, {"source": "73", "target": "82", "source_name": "room temperature", "target_name": "insertion loss", "weight": 1.0, "year": 2021}, {"source": "73", "target": "84", "source_name": "room temperature", "target_name": "ground state", "weight": 3.0, "year": 2021}, {"source": "73", "target": "85", "source_name": "room temperature", "target_name": "perturbation theory", "weight": 1.0, "year": 2021}, {"source": "73", "target": "87", "source_name": "room temperature", "target_name": "charge transfer", "weight": 2.0, "year": 2021}, {"source": "73", "target": "88", "source_name": "room temperature", "target_name": "energy storage", "weight": 2.0, "year": 2021}, {"source": "73", "target": "90", "source_name": "room temperature", "target_name": "cooper pair", "weight": 5.0, "year": 2021}, {"source": "73", "target": "92", "source_name": "room temperature", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "74", "target": "75", "source_name": "transmission line", "target_name": "stainless steel", "weight": 1.0, "year": 2021}, {"source": "74", "target": "88", "source_name": "transmission line", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "75", "target": "76", "source_name": "stainless steel", "target_name": "heat exchanger", "weight": 1.0, "year": 2021}, {"source": "75", "target": "77", "source_name": "stainless steel", "target_name": "magnetic levitation", "weight": 1.0, "year": 2021}, {"source": "77", "target": "83", "source_name": "magnetic levitation", "target_name": "permanent magnet", "weight": 6.0, "year": 2021}, {"source": "77", "target": "88", "source_name": "magnetic levitation", "target_name": "energy storage", "weight": 3.0, "year": 2021}, {"source": "78", "target": "79", "source_name": "charge carrier", "target_name": "crystal structure", "weight": 2.0, "year": 2021}, {"source": "78", "target": "84", "source_name": "charge carrier", "target_name": "ground state", "weight": 1.0, "year": 2021}, {"source": "78", "target": "90", "source_name": "charge carrier", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "79", "target": "84", "source_name": "crystal structure", "target_name": "ground state", "weight": 2.0, "year": 2021}, {"source": "79", "target": "85", "source_name": "crystal structure", "target_name": "perturbation theory", "weight": 3.0, "year": 2021}, {"source": "79", "target": "90", "source_name": "crystal structure", "target_name": "cooper pair", "weight": 2.0, "year": 2021}, {"source": "79", "target": "91", "source_name": "crystal structure", "target_name": "heat capacity", "weight": 2.0, "year": 2021}, {"source": "79", "target": "92", "source_name": "crystal structure", "target_name": "ab initio", "weight": 5.0, "year": 2021}, {"source": "80", "target": "81", "source_name": "quench propagation", "target_name": "finite element", "weight": 3.0, "year": 2021}, {"source": "81", "target": "83", "source_name": "finite element", "target_name": "permanent magnet", "weight": 3.0, "year": 2021}, {"source": "81", "target": "86", "source_name": "finite element", "target_name": "induction motor", "weight": 3.0, "year": 2021}, {"source": "81", "target": "88", "source_name": "finite element", "target_name": "energy storage", "weight": 1.0, "year": 2021}, {"source": "83", "target": "86", "source_name": "permanent magnet", "target_name": "induction motor", "weight": 1.0, "year": 2021}, {"source": "83", "target": "88", "source_name": "permanent magnet", "target_name": "energy storage", "weight": 4.0, "year": 2021}, {"source": "84", "target": "90", "source_name": "ground state", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "87", "target": "90", "source_name": "charge transfer", "target_name": "cooper pair", "weight": 4.0, "year": 2021}, {"source": "87", "target": "92", "source_name": "charge transfer", "target_name": "ab initio", "weight": 1.0, "year": 2021}, {"source": "88", "target": "90", "source_name": "energy storage", "target_name": "cooper pair", "weight": 1.0, "year": 2021}, {"source": "91", "target": "92", "source_name": "heat capacity", "target_name": "ab initio", "weight": 1.0, "year": 2021}]}]}