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2016-12-16
Scheme variations of the QCD coupling and tau decays
The QCD coupling, $\alpha_s$, is not a physical observable since it depends on conventions related to the renormalization procedure. Here we discuss a redefinition of the coupling where changes of scheme are parametrised by a single parameter $C$. The new coupling is denoted $\hat \alpha_s$ and its running is scheme in...
1612.05558v1
2016-12-20
The mean field analysis for the Kuramoto model on graphs I. The mean field equation and transition point formulas
In his classical work on synchronization, Kuramoto derived the formula for the critical value of the coupling strength corresponding to the transition to synchrony in large ensembles of all-to-all coupled phase oscillators with randomly distributed intrinsic frequencies. We extend the Kuramoto's result to a large class...
1612.06493v1
2016-12-20
Time evolution of coupled spin systems in a generalized Wigner representation
Phase-space representations as given by Wigner functions are a powerful tool for representing the quantum state and characterizing its time evolution in the case of infinite-dimensional quantum systems and have been widely used in quantum optics and beyond. Continuous phase spaces have also been studied for finite-dime...
1612.06777v2
2016-12-29
Ultrastrong-coupling quantum-phase-transition phenomena in a few-qubit circuit QED system
We study ultrastrong-coupling quantum-phase-transition phenomena in a few-qubit system. In the one-qubit case, three second-order transitions occur and the Goldstone mode emerges under the condition of ultrastrong-coupling strength. Moreover, a first-order phase transition occurs between two different superradiant phas...
1612.09119v2
2016-12-30
Impurity-Induced Environmental Quantum Phase Transitions in the Quadratic-Coupling Spin-Boson Model
We study the zero temperature properties of the sub-Ohmic spin-boson model with quadratic spin-boson coupling. This model describes experimental set ups at the optimal working point where the linear-coupling between the qubit (spin) and the environmental noise (bosons) is zero and the leading coupling is quadratic. In ...
1612.09437v2
2017-07-05
Universal stabilization of a parametrically coupled qubit
We autonomously stabilize arbitrary states of a qubit through parametric modulation of the coupling between a fixed frequency qubit and resonator. The coupling modulation is achieved with a tunable coupler design, in which the qubit and the resonator are connected in parallel to a superconducting quantum interference d...
1707.01491v1
2017-07-10
Strong 4-mode coupling of nanomechanical string resonators
We investigate mechanical mode coupling between the four fundamental flexural modes of two doubly-clamped, high-Q silicon-nitride nanomechanical string resonators. Strong mechanical coupling between the strings is induced by the strain mediated via a shared clamping point, engineered to increase the exchange of oscilla...
1707.02926v3
2017-07-13
Density matrix renormalization group study of a three-orbital Hubbard model with spin-orbit coupling in one dimension
Using the Density Matrix Renormalization Group technique we study the effect of spin-orbit coupling on a three-orbital Hubbard model in the $(t_{2g})^{4}$ sector and in one dimension. Fixing the Hund coupling to a robust value compatible with some multiorbital materials, we present the phase diagram varying the Hubbard...
1707.04313v1
2017-07-19
Coupled DM heating in SCDEW cosmologies
Strongly Coupled Dark Energy plus Warm dark matter (SCDEW) cosmologies admit the stationary presence of $\sim 1\, \%$ of coupled-DM and DE, since inflationary reheating. Coupled-DM fluctuations therefore grow up to non-linearity even in the early radiative expansion. Such early non-linear stages are modelized here thro...
1707.06004v2
2017-07-21
Exact Cancellation of Emittance Due to Coupled Transverse Dynamics in Solenoids and RF Couplers
Small, stray magnetic and RF fields in electron guns and injectors can perturb an electron beam and introduce correlations between the otherwise orthogonal transverse trajectories. These correlations couple the x and y dynamics which increases the transverse emittance. If the correlation becomes "diluted" or randomized...
1707.07015v1
2017-11-01
Negative differential thermal conductance and heat amplification in a nonequilibrium triangle-coupled spin-boson system at strong coupling
We investigate the nonequilibrium quantum heat transfer in a triangle-coupled spin-boson system within a three-terminal setup. By including the nonequilibrium noninteracting blip approximation approach combined with the full counting statistics, we analytically obtain the steady state populations and heat currents. The...
1711.00204v1
2017-11-03
Coupling of nanoparticle dynamics to polymer center-of-mass motion in semidilute polymer solutions
We investigate the dynamics of nanoparticles in semidilute polymer solutions when the nanoparticles are comparably sized to the polymer coils using explicit- and implicit-solvent simulation methods. The nanoparticle dynamics are subdiffusive on short time scales before transitioning to diffusive motion on long time sca...
1711.01014v3
2017-11-05
Multi-mode superconducting circuits for realizing strongly coupled multi-qubit processor units
Inter-qubit coupling and qubit connectivity in a processor are crucial for achieving high fidelity multi-qubit gates and efficient implementation of quantum algorithms. Typical superconducting processors employ relatively weak transverse inter-qubit coupling which are activated via frequency tuning or microwave drives....
1711.01658v3
2017-11-06
Coherent spin-qubit photon coupling
Electron spins hold great promise for quantum computation due to their long coherence times. An approach to realize interactions between distant spin-qubits is to use photons as carriers of quantum information. We demonstrate strong coupling between single microwave photons in a NbTiN high impedance cavity and a three-...
1711.01932v1
2017-11-06
Crosstalk error correction through dynamical decoupling of single-qubit gates in capacitively coupled singlet-triplet semiconductor spin qubits
In addition to magnetic field and electric charge noise adversely affecting spin qubit operations, performing single-qubit gates on one of multiple coupled singlet-triplet qubits presents a new challenge---crosstalk, which is inevitable (and must be minimized) in any multiqubit quantum computing architecture. We develo...
1711.02092v2
2017-11-07
Spin-Orbit Coupling and Magnetic Anisotropy in Iron-Based Superconductors
We determine theoretically the effect of spin-orbit coupling on the magnetic excitation spectrum of itinerant multi-orbital systems, with specific application to iron-based superconductors. Our microscopic model includes a realistic ten-band kinetic Hamiltonian, atomic spin-orbit coupling, and multi-orbital Hubbard int...
1711.02460v1
2017-11-16
Yu-Shiba-Rusinov screening of spins in double quantum dots
A magnetic impurity coupled to a superconductor gives rise to a Yu-Shiba-Rusinov (YSR) state inside the superconducting energy gap. With increasing exchange coupling the excitation energy of this state eventually crosses zero and the system switches to a YSR groundstate with bound quasiparticles screening the impurity ...
1711.06081v1
2017-11-17
Enhancement of Electromagnetically Induced Transparency in Metamaterials Using Long Range Coupling Mediated by a Hyperbolic Material
Near-field coupling is a fundamental physical effect, which plays an important role in the establishment of classical analog of electromagnetically induced transparency (EIT). However, in a normal environment the coupling length between the bright and dark artificial atoms is very short and far less than one wavelength...
1711.06522v2
2017-11-18
Topological edge states and pumping in a chain of coupled superconducting qubits
Topological insulators have inspired the study with various quantum simulators. Exploiting the tunability of the qubit frequency and qubit-qubit coupling, we show that a superconducting qubit chain can simulate various topological band models. When the system is restricted to the single-spin excitation subspace, the Su...
1711.06829v1
2017-11-23
Herring-Flicker coupling and thermal quantum correlations in bipartite system
In this letter we study thermal quantum correlations as quantum discord and entanglement in bipartite system imposed by external magnetic field with Herring-Flicker coupling ie. $J(R)=1.642 e^{-2 R} R^{5/2}+O(R^{2}e^{-2R})$. The Herring-Flicker coupling strength is the function of $R$, which is the distance between spi...
1711.08620v3
2017-11-27
Reaching the optomechanical strong coupling regime with a single atom in a cavity
A major goal within the field of optomechanics is to achieve the single-photon strong coupling regime, wherein even a mechanical displacement as small as the zero-point uncertainty is enough to shift an optical cavity resonance by more than its linewidth. This goal is difficult, however, due to the small zero-point mot...
1711.09619v2
2017-11-29
Production of gravitational waves during preheating with nonminimal coupling
We study the preheating and the in-process production of gravitational waves (GWs) after inflation in which the inflaton is nonminimally coupled to the curvature in a self-interacting quartic potential with the method of lattice simulation. We find that the nonminimal coupling enhances the amplitude of the density spec...
1711.10888v3
2018-10-10
Collective modes of two-dimensional classical Coulomb fluids
Molecular dynamics simulations have been performed to investigate in detail collective modes spectra of two-dimensional Coulomb fluids in a wide range of coupling. The obtained dispersion relations are compared with theoretical approaches based on quasi-crystalline approximation (QCA), also known as the quasi-localized...
1810.04435v1
2018-10-13
Dynamical properties of the finite-size Dicke model coupled to a thermal reservoir
We investigate the dynamical properties of the finite-size Dicke model coupled to a photon reservoir in the dispersive regime. The system-reservoir coupling in our Hamiltonian includes counter-rotating terms, which are relevant in the strong atom-cavity coupling. Because the dispersive regime is considered, the dynamic...
1810.05888v1
2018-10-22
Dynamics of a quantum oscillator coupled with a three-level Lambda-type emitter
We investigate the quantum dynamics of a quantum oscillator coupled with the most upper state of a three-level $\Lambda-$ type system. The two transitions of the three-level emitter, possessing orthogonal dipole moments, are coherently pumped with a single or two electromagnetic field sources, respectively. We have fou...
1810.09264v2
2018-10-22
Matching renormalisable couplings: simple schemes and a plot
We discuss different choices that can be made when matching a general high-energy theory -- with the restriction that it should not contain heavy gauge bosons -- onto a general renormalisable effective field theory at one loop, with particular attention to the quartic scalar couplings and Yukawa couplings. This include...
1810.09388v2
2018-10-27
Anomalous triple gauge boson couplings in $ZZ$ production at the LHC and the role of $Z$ boson polarizations
We study anomalous couplings among neutral gauge bosons in $ZZ$ production at the LHC for $\sqrt{s}=13$ TeV in $4$-lepton final state. We use the cross section and polarization asymmetries of the $Z$ boson to estimate simultaneous limits on anomalous coupling using Markov-Chain--Monte-Carlo (MCMC) method for luminositi...
1810.11657v3
2018-10-30
Top-bottom-tau Yukawa coupling unification in the MSSM+1VF and fermion masses as IR fixed points
In the MSSM extended by a complete vectorlike family, precise top, bottom and tau Yukawa coupling unification can be achieved assuming SUSY threshold corrections which are typical for comparable superpartner masses. Furthermore, the unification is possible with a large unified coupling, implying that all three fermion ...
1810.12474v2
2018-10-31
Minimal Surfaces and Generalized Einstein-Maxwell-dilaton Theory
We present novel classes of non-stationary solutions to the five-dimensional generalized Einstein-Maxwell-dilaton theory with cosmological constant, in which the Maxwell's filed and the cosmological constant couple to the dilaton field. In the first class of solutions, the two non-zero coupling constants are different ...
1810.13051v2
2019-05-02
Subradiance dynamics in a singly-excited chiral-coupled atomic chain
We theoretically investigate the subradiance dynamics in a nonreciprocal chiral-coupled atomic chain, in which infinite-range dipole-dipole interaction emerges in the dissipation. We find that super- and subradiance are both present in the dissipation process following single photon excitation, and the decay dynamics s...
1905.00558v2
2019-05-03
Mott polaritons in cavity-coupled quantum materials
We show that strong electron-electron interactions in cavity-coupled quantum materials can enable collectively enhanced light-matter interactions with ultrastrong effective coupling strengths. As a paradigmatic example we consider a Fermi-Hubbard model coupled to a single-mode cavity and find that resonant electron-cav...
1905.02044v1
2019-05-14
The Dark Matter Phonon Coupling
Generically, the effective coupling between the dark matter and an atom scales with the number of constituents in the atom, resulting in the effective coupling being proportional to the mass of the atom. In this limit, when the momentum transfer is also small, we show that the leading term in the scattering of a partic...
1905.05575v2
2019-05-15
Hybrid plasmonic waveguide coupling of photons from a single molecule
We demonstrate the emission of photons from a single molecule into a hybrid gap plasmon waveguide (HGPW). Crystals of anthracene, doped with dibenzoterrylene (DBT), are grown on top of the waveguides. We investigate a single DBT molecule coupled to the plasmonic region of one of the guides, and determine its in-plane o...
1905.06321v1
2019-05-17
Observation of Multimode Strong Coupling of Cold Atoms to a 30-m Long Optical Resonator
We report on the observation of multimode strong coupling of a small ensemble of atoms interacting with the field of a 30-m long fiber resonator containing a nanofiber section. The collective light--matter coupling strength exceeds the free spectral range and the atoms couple to consecutive longitudinal resonator modes...
1905.07353v1
2019-05-21
Effective Spin-2 Quasi-particles at Linear Dispersive Five-fold Degenerate Points with Tunable Topological Chern Numbers
In this work, which is based on spin-2 vectors and traceless spin-2 tensors, an effective Hamiltonian is constructed with a linearly dispersive five-fold degenerate point with spin-2 vector-momentum couplings. For the model without spin-2 vector-tensor coupling, the topological Chern numbers of five bands are calculate...
1905.08435v1
2019-05-21
Induced spin-orbit coupling in twisted graphene-TMDC heterobilayers: twistronics meets spintronics
We propose an interband tunneling picture to explain and predict the interlayer twist angle dependence of the induced spin-orbit coupling in heterostructures of graphene and monolayer transition metal dichalcogenides (TMDCs). We obtain a compact analytic formula for the induced valley Zeeman and Rashba spin-orbit coupl...
1905.08688v1
2019-05-27
On the impact of Majorana masses in gravity-matter systems
We investigate the Higgs-Yukawa system with Majorana masses of a fermion within asymptotically safe quantum gravity. Using the functional renormalization group method we derive the beta functions of the Majorana masses and the Yukawa coupling constant and discuss the possibility of a non-trivial fixed point for the Yuk...
1905.11114v2
2019-05-29
Entanglement and quantum discord in optically coupled coherent Ising machines
We present analytical and numerical simulation results for squeezing, entanglement, and quantum discord in a dissipatively coupled coherent Ising machine (CIM). Both analytical solutions and numerical simulation results, which are obtained with positive-P, truncated-Wigner and truncated-Husimi representations for the d...
1905.12348v2
2019-05-29
Higgs Parity Grand Unification
The vanishing of the Higgs quartic coupling of the Standard Model at high energies may be explained by spontaneous breaking of Higgs Parity. Taking Higgs Parity to originate from the Left-Right symmetry of the $SO(10)$ gauge group, leads to a new scheme for precision gauge coupling unification that is consistent with p...
1905.12722v1
2019-05-31
Aspects of wave turbulence in preheating II: Rebirth of the nonminimal coupled models
We study the nonlinear stage of preheating in a model consisting of a single inflaton field $\phi$ nonminimally coupled to the spacetime curvature and considering a self-coupling quartic potential V ($\phi$) = $\lambda \phi^4/4$. As the first motivation, we mention that this nonminimally coupled model agrees with the o...
1905.13647v1
2020-05-30
Complex Sequential Understanding through the Awareness of Spatial and Temporal Concepts
Understanding sequential information is a fundamental task for artificial intelligence. Current neural networks attempt to learn spatial and temporal information as a whole, limited their abilities to represent large scale spatial representations over long-range sequences. Here, we introduce a new modeling strategy cal...
2006.00212v1
2020-06-14
Efficient Approximate Minimum Entropy Coupling of Multiple Probability Distributions
Given a collection of probability distributions $p_{1},\ldots,p_{m}$, the minimum entropy coupling is the coupling $X_{1},\ldots,X_{m}$ ($X_{i}\sim p_{i}$) with the smallest entropy $H(X_{1},\ldots,X_{m})$. While this problem is known to be NP-hard, we present an efficient algorithm for computing a coupling with entrop...
2006.07955v2
2020-06-16
Generating Giant Vortex in a Fermi Superfluid via Spin-Orbital-Angular-Momentum Coupling
Spin-orbital-angular-momentum (SOAM) coupling has been realized in recent experiments of Bose-Einstein condensates [Chen et al., Phys. Rev. Lett. 121, 113204 (2018) and Zhang et al., Phys. Rev. Lett. 122, 110402 (2019)], where the orbital angular momentum imprinted upon bosons leads to quantized vortices. For fermions,...
2006.08898v2
2020-06-16
Multipole analysis of substrate-supported dielectric nanoresonator arrays with T-matrix method
Substrates, and layered media in general, are ubiquitous, affect the properties of whatever is in their vicinity, and their influence is, in an arbitrary framework, challenging to quantify analytically, especially for large arrays which escape explicit numerical treatment due to the computational burden. In this work, ...
2006.09137v1
2020-06-20
Tunable magnon-magnon coupling in synthetic antiferromagnets
In this work, we study magnon-magnon coupling in synthetic antiferromagnets (SyAFs) using microwave spectroscopy at room temperature. Two distinct spin-wave modes are clearly observed and are hybridised at degeneracy points. We provide a phenomenological model that captures the coupling phenomena and experimentally dem...
2006.11633v2
2020-06-21
Forces and Torques Near to Impact in the Golf Swing
Motivated by MacKenzie's observation of a negative force couple near to impact, this paper explores a model for how the golf club moves near to impact. It assumes the golf club is moving as the distal arm of a double pendulum. At impact the club head is moving straight down the target line, at its maximum speed, on a p...
2006.11778v1
2020-06-22
Effective coupling conditions for arbitrary flows in Stokes-Darcy systems
Boundary conditions at the interface between the free-flow region and the adjacent porous medium is a key issue for physically consistent modeling and accurate numerical simulation of flow and transport processes in coupled systems due to the interface driven nature of such processes. Interface conditions available in ...
2006.12096v1
2020-06-24
Optimal storage time for $N$ qubits coupled to a one-dimensional waveguide
Symmetry-protected subradiance is known to guarantee high qubit storage times in free space. We show that in one-dimensional waveguides, this is also true, but that even longer qubit storage times can be identified by considering the eigenspectrum of the qubit-qubit coupling matrix. In the process, we introduce three t...
2006.14020v1
2020-06-27
A Comprehensible Review: Magnonic Magnetoelectric Coupling in Ferroelectric/ Ferromagnetic Composites
Composite materials consisting of coupled magnetic and ferroelectric layers hold the promise for new emergent properties such as controlling magnetism with electric fields. Obviously, the interfacial coupling mechanism plays a crucial role and its understanding is the key for exploiting this material class for technolo...
2006.15290v2
2020-09-02
Perfect coherent transfer in an on-chip reconfigurable nanoelectromechanical network
Realizing a controllable network with multiple degrees of interaction is a challenge to physics and engineering. Here, we experimentally report an on-chip reconfigurable network based on nanoelectromechanical resonators with nearest-neighbor (NN) and next-nearest-neighbor (NNN) strong couplings. By applying different p...
2009.00798v2
2020-09-03
Quantum Zeno effects across a parity-time symmetry breaking transition in atomic momentum space
We experimentally study quantum Zeno effects in a parity-time (PT) symmetric cold atom gas periodically coupled to a reservoir. Based on the state-of-the-art control of inter-site couplings of atoms in a momentum lattice, we implement a synthetic two-level system with passive PT symmetry over two lattice sites, where a...
2009.01419v1
2020-09-04
Spectroscopy and critical quantum thermometry in the ultrastrong coupling regime
We present an exact analytical solution of the anisotropic Hopfield model, and we use it to investigate in detail the spectral and thermometric response of two ultrastrongly coupled quantum systems. Interestingly, we show that depending on the initial state of the coupled system, the vacuum Rabi splitting manifests sig...
2009.01994v2
2020-09-09
Effect of dipolar interactions on cavity magnon-polaritons
The strong photon-magnon coupling between an electromagnetic cavity and two yttrium iron garnet (YIG) spheres has been investigated in the context of a strong mutual dipolar interaction between the spheres. A decrease in the coupling strength between the YIG spheres and the electromagnetic cavity is observed, along wit...
2009.04557v1
2020-09-15
Lattice N=4 super Yang-Mills at Strong Coupling
In this paper we present results from numerical simulations of N=4 super Yang-Mills for two color gauge theory over a wide range of 't Hooft coupling $0<\lambda\le 30$ using a supersymmetric lattice action \cite{Catterall:2009it}. Numerical study of this lattice theory has been stymied until recently by both sign probl...
2009.07334v2
2020-09-19
Koopman analysis in oscillator synchronization
Synchronization is an important dynamical phenomenon in coupled nonlinear systems, which has been studied extensively in recent years. However, analysis focused on individual orbits seems hard to extend to complex systems while a global statistical approach is overly cursory. Koopman operator technique seems to well ba...
2009.09227v1
2020-09-26
Holograhic two-currents model with coupling and its conductivites
We implement a holographic gravity model of two gauge fields with a coupling between them, which is dual to a two-currents model. An analytical black brane solution is obtained. In particular, we work out the expressions of conductivities with coupling and find that the expressions of conductivities are directly relate...
2009.12556v1
2020-09-30
Rashba coupling and spin switching through surface states of Dirac semimetals
We study the effect of the Rashba spin-orbit coupling on the Fermi arcs of topological Dirac semimetals. The Rashba coupling is induced by breaking the inversion symmetry at the surface. Remarkably, this coupling could be enhanced by the interaction with the substrate and controlled by an external electric field. We st...
2009.14753v2
2021-02-09
Axion induced spin effective couplings
Detecting axionic dark matter induced electron or nucleon oscillating electric dipole moment (OEDM) has become a new way for dark matter searches. We re-examine such axion-spin couplings in external electromagnetic fields. We point out that axion-photon interaction induces an electron spin effective coupling, which is ...
2102.04669v1
2021-02-02
Chimeras and clusters emerging from robust-chaos dynamics
We show that dynamical clustering, where a system segregates into distinguishable subsets of synchronized elements, and chimera states, where differentiated subsets of synchronized and desynchronized elements coexist, can emerge in networks of globally coupled robust-chaos oscillators. We describe the collective behavi...
2102.06087v1
2021-02-17
Sharp Boundaries for the Swampland
We reconsider the problem of bounding higher derivative couplings in consistent weakly coupled gravitational theories, starting from general assumptions about analyticity and Regge growth of the S-matrix. Higher derivative couplings are expected to be of order one in the units of the UV cutoff. Our approach justifies t...
2102.08951v2
2021-02-18
Subgrid multiscale stabilized finite element analysis of non-Newtonian Power-law model fully coupled with Advection-Diffusion-Reaction equations
This article presents stability and convergence analyses of subgrid multiscale stabilized finite element formulation of non-Newtonian power-law fluid flow model strongly coupled with variable coefficients Advection-Diffusion-Reaction ($VADR$) equation. Considering the highly non-linear viscosity coefficient as solute c...
2102.09170v1
2021-02-19
Axion-matter coupling in multiferroics
Multiferroics (MFs) are materials with two or more ferroic orders, like spontaneous ferroelectric and ferromagnetic polarizations. Such materials can exhibit a magnetoelectric effect whereby magnetic and ferroelectric polarizations couple linearly, reminiscent of, but not identical to the electromagnetic $\boldsymbol{E...
2102.10171v2
2021-02-23
Limit on Higgs boson trilinear self-coupling in coupled technicolor models
The trilinear self-coupling of the Higgs boson, in a theory in which this boson is composite, is compared to the experimental bound of this quantity obtained by the CMS experiment. In the case of a model where technicolor (TC) is coupled to QCD, we find that the experimental result already constrain the dynamics of the...
2102.11709v3
2021-02-23
Tunable Cooperativity in Coupled Spin--Cavity Systems
We experimentally study the tunability of the cooperativity in coupled spin--cavity systems by changing the magnetic state of the spin system via an external control parameter. As model system, we use the skyrmion host material Cu$_2$OSeO$_3$ coupled to a microwave cavity resonator. In the different magnetic phases we ...
2102.11713v1
2013-06-11
Estimates for the Thermal Width of Heavy Quarkonia in Strongly Coupled Plasmas from Holography
The gauge/gravity duality is used to investigate the imaginary part of the heavy quark potential (defined via the rectangular Wilson loop) in strongly coupled plasmas. This quantity can be used to estimate the width of heavy quarkonia in a plasma at strong coupling. In this paper the thermal worldsheet fluctuation meth...
1306.2613v2
2013-06-12
Atomic spin-orbit coupling synthesized with magnetic-field-gradient pulses
We discuss a general scheme for creating atomic spin-orbit coupling (SOC) such as the Rashba or Dresselhaus types using magnetic-field-gradient pulses. In contrast to conventional schemes based on adiabatic center-of-mass motion with atomic internal states restricted to a dressed-state subspace, our scheme works for th...
1306.2829v1
2013-06-12
Dissipative dynamics of a driven quantum spin coupled to a bath of ultracold fermions
We explore the dynamics and the steady state of a driven quantum spin coupled to a bath of fermions, which can be realized with a strongly imbalanced mixture of ultracold atoms using currently available experimental tools. Radio-frequency driving can be used to induce tunneling between the spin states. The Rabi oscilla...
1306.2947v2
2013-06-14
Localized modes in dense repulsive and attractive Bose-Einstein condensates with spin-orbit and Rabi couplings
We consider a binary Bose-Einstein condensate with linear and nonlinear interactions between its components, which emulate the spinor system with spin-orbit (SO) and Rabi couplings. For a relatively dense condensate, 1D coupled equations with the nonpolynomial nonlinearity of both repulsive and attractive signs are der...
1306.3402v1
2013-06-19
Spin-Orbit Coupling Induced Coherent Production of Feshbach Molecules in a Degenerate Fermi Gas
In this work we demonstrate a dynamic process in which SO coupling can coherently produce s-wave Feshbach molecules from a fully polarized Fermi gas, and can induce a coherent oscillation between Feshbach molecules and spin polarized gas. For comparison, we also show that such phenomena are absent if the inter-componen...
1306.4568v2
2015-07-01
Controlling photon transport in the single-photon weak-coupling regime of cavity optomechanics
We study the photon statistics properties of few-photon transport in an optomechanical system where an optomechanical cavity couples to two empty cavities. By analytically deriving the one- and two-photon currents in terms of a zero-time-delayed two-order correlation function, we show that a photon blockade can be achi...
1507.00178v1
2015-07-01
Dynamical spin-density waves in a spin-orbit-coupled Bose-Einstein condensate
Synthetic spin-orbit (SO) coupling, an important ingredient for quantum simulation of many exotic condensed matter physics, has recently attracted considerable attention. The static and dynamic properties of a SO coupled Bose-Einstein condensate (BEC) have been extensively studied in both theory and experiment. Here we...
1507.00318v1
2015-07-07
Approximating electronically excited states with equation-of-motion linear coupled-cluster theory
A new perturbative approach to canonical equation-of-motion coupled-cluster theory is presented using coupled-cluster perturbation theory. A second-order M{\o}ller-Plesset partitioning of the Hamiltonian is used to obtain the well known equation-of-motion many-body perturbation theory (EOM-MBPT(2)) equations and two ne...
1507.01969v1
2015-07-13
Coupling quantum circuits to magnetic molecular qubits
This thesis explores the coupling of magnetic systems to quantum circuits in the context of quantum computing applications. In particular we study the coupling of superconducting coplanar waveguide resonators to Single Molecule Magnets (SMMs) . The combination of approaches from the fields of Cavity Quantum electrodyna...
1507.03579v2
2015-12-04
Isotropy of Angular Frequencies and Weak Chimeras With Broken Symmetry
The notion of a weak chimeras provides a tractable definition for chimera states in networks of finitely many phase oscillators. Here we generalize the definition of a weak chimera to a more general class of equivariant dynamical systems by characterizing solutions in terms of the isotropy of their angular frequency ve...
1512.01321v4
2015-12-08
Multi-orbital quantum antiferromagnetism in iron pnictides --- effective spin couplings and quantum corrections to sublattice magnetization
Towards understanding the multi-orbital quantum antiferromagnetism in iron pnictides, effective spin couplings and spin fluctuation induced quantum corrections to sublattice magnetization are obtained in the $(\pi,0)$ AF state of a realistic three band interacting electron model involving $xz$, $yz$, and $xy$ Fe 3d orb...
1512.02398v1
2015-12-09
Ground-state cooling of dispersively coupled optomechanical system in unresolved sideband regime via dissipatively coupled oscillator
In the optomechanical cooling of a dispersively coupled oscillator, it is only possible to reach the oscillator ground state in the resolved sideband regime, where the cavity-mode line width is smaller than the resonant frequency of the mechanical oscillator being cooled. In this paper, we show that the dispersively co...
1512.02795v2
2015-12-14
Anderson Localization in Degenerate Spin-Orbit Coupled Fermi Gases with Disorder
Competition between superconductivity and disorder plays an essential role in understanding the metal-insulator transition. Based on the Bogoliubov-de Gennes equation, we studied an s-wave superconductor with both spin-orbit coupling and disorder are presented. With increasing the strength of disorder, the mean superco...
1512.04211v2
2015-12-16
Escaping in couples facilitates evacuation: Experimental study and modeling
In this paper, the impact of escaping in couples on the evacuation dynamics has been investigated via experiments and modeling. Two sets of experiments have been implemented, in which pedestrians are asked to escape either in individual or in couples. The experiments show that escaping in couples can decrease the avera...
1512.05120v1
2015-12-18
Gravitational Collapse of a Homogeneous Scalar Field Coupled Kinematically to Einstein Tensor
We study the gravitational collapse of a homogeneous time-dependent scalar field that, besides its coupling to curvature, it is also kinematically coupled to the Einstein tensor. This coupling is a part of the Horndeski theory and we investigate its effect on the collapsing process. We find that the time required for t...
1512.05934v4
2015-12-18
Geodesic acoustic modes with poloidal mode couplings ad infinitum
Geodesic acoustic modes (GAMs) are studied, for the first time, including all poloidal mode $(m)$ couplings using drift reduced fluid equations. The nearest neighbor coupling pattern, due to geodesic curvature, leads to a semi-infinite chain model of the GAM with the mode-mode coupling matrix elements proportional to t...
1512.06066v1
2015-12-20
Semi-Holography for Heavy Ion Collisions: Self-Consistency and First Numerical Tests
We present an extended version of a recently proposed semi-holographic model for heavy-ion collisions, which includes self-consistent couplings between the Yang-Mills fields of the Color Glass Condensate framework and an infrared AdS/CFT sector, such as to guarantee the existence of a conserved energy-momentum tensor f...
1512.06445v2
2015-12-22
Dark matter from gravitational particle production at reheating
We show that curvature induced particle production at reheating generates adiabatic dark matter if there are non-minimally coupled spectator scalars weakly coupled to visible matter. The observed dark matter abundance implies an upper bound on spectator masses $m$ and non-minimal coupling values $\xi$. For example, ass...
1512.07288v4
2015-12-23
Bose-Einstein condensate in an optical lattice with Raman-assisted two-dimensional spin-orbit coupling
In a recent experiment by Wu {\textit et al.} (arXiv:1511.08170), a Raman-assisted two-dimensional spin-orbit coupling has been realized for a Bose-Einstein condensate in an optical lattice potential. In light of this exciting progress, we study in detail key properties of the system. As the Raman lasers inevitably cou...
1512.07448v3
2015-12-24
Stabilizing coherence with nested environments: a numerical study using kicked Ising models
We study a tripartite system of coupled spins, where a first set of one or two spins is our central system which is coupled to another set considered, the near environment, in turn coupled to the third set, the far environment. The dynamics considered are those of a generalized kicked spin chain in the regime of quantu...
1512.07683v1
2015-12-26
Classical and Quantum Stability in Putative Landscapes
Landscape analyses often assume the existence of large numbers of fields, $N$, with all of the many couplings among these fields (subject to constraints such as local supersymmetry) selected independently and randomly from simple (say Gaussian) distributions. We point out that unitarity and perturbativity place signifi...
1512.08125v3
2015-12-30
Higher-Derivative Gravity with Non-minimally Coupled Maxwell Field
We construct higher-derivative gravities with a non-minimally coupled Maxwell field. The Lagrangian consists of polynomial invariants built from the Riemann tensor and the Maxwell field strength in such a way that the equations of motion are second order for both the metric and the Maxwell potential. We also generalize...
1512.09153v1
2015-12-31
Optimised multi-ion cavity coupling
Recent technological advances in cavity quantum electrodynamics (CQED) are paving the way to utilise multiple quantum emitters confined in a single optical cavity. In such systems it is crucially important to control the quantum mechanical coupling of individual emitters to the cavity mode. In this regard, combining io...
1512.09346v1
2016-09-02
Influence of coupling on thermal forces and dynamic friction in plasmas with multiple ion species
The recently proposed effective potential theory [Phys. Rev. Lett. 110, 235001 (2013)] is used to investigate the influence of coupling on inter-ion-species diffusion and momentum exchange in multi-component plasmas. Thermo-diffusion and the thermal force are found to diminish rapidly as strong coupling onsets. For the...
1609.00742v4
2016-09-05
Landau-Zener transitions in an open multilevel quantum system
We consider the Landau-Zener problem for a multilevel quantum system that is coupled to an external environment. In particular, we consider a number of cases of three-level systems coupled to a harmonic oscillator that represents the external environment. We find that, similar to the case of the Landau-Zener problem wi...
1609.01150v2
2016-09-06
Multiple Rabi Splittings under Ultra-Strong Vibrational Coupling
From the high vibrational dipolar strength offered by molecular liquids, we demonstrate that a molecular vibration can be ultra-strongly coupled to multiple IR cavity modes, with Rabi splittings reaching $24\%$ of the vibration frequencies. As a proof of the ultra-strong coupling regime, our experimental data unambiguo...
1609.01520v1
2016-09-06
Possible Explanation of the Electron Positron Anomaly at 17 MeV in $^8Be$ Transitions Through a Light Pseudoscalar
We estimate the values of Yukawa couplings of a light pseudoscalar A with a mass of about 17 MeV, which would explain the $^8Be$ anomaly observed in the Atomki pair spectrometer experiment. The resulting couplings of A to up and down type quarks are about 0.3 times the coupling of the standard Higgs boson. Then constra...
1609.01669v2
2016-09-07
Bifurcations observed in the spectra of coupled electron-phonon modes in multiferroic $PrFe_3(BO_3)_4$ subjected to a magnetic field
We report on bifurcations effect mediated by the electron-phonon coupling in a concentrated rare-earth-containing antiferromagnet, observed in the spectra of coupled $4f$-electron-phonon modes under the influence of an external magnetic field. The effect was observed in the low-temperature far-infrared (terahertz) refl...
1609.02125v1
2016-09-08
Principal modes in multimode fibers: exploring the crossover from weak to strong mode coupling
We present experimental and numerical studies on principal modes in a multimode fiber with mode coupling. By applying external stress to the fiber and gradually adjusting the stress, we have realized a transition from weak to strong mode coupling, which corresponds to the transition from single scattering to multiple s...
1609.02516v1
2016-09-08
Fate of the one-dimensional Ising quantum critical point coupled to a gapless boson
The problem of a quantum Ising degree of freedom coupled to a gapless bosonic mode appears naturally in many one dimensional systems, yet surprisingly little is known how such a coupling affects the Ising quantum critical point. We investigate the fate of the critical point in a regime, where the weak coupling renormal...
1609.02599v3
2016-09-14
Inhibitory loop robustly induces anticipated synchronization in neuronal microcircuits
We investigate the synchronization properties between two excitatory coupled neurons in the presence of an inhibitory loop mediated by an interneuron. Dynamical inhibition together with noise independently applied to each neuron provide phase diversity in the dynamics of the neuronal motif. We show that the interplay b...
1609.04419v1
2016-09-15
Diffused vorticity and moment of inertia of a spin-orbit coupled Bose-Einstein condensate
By developing the hydrodynamic theory of spinor superfluids we calculate the moment of inertia of a harmonically trapped Bose-Einstein condensate with spin-orbit coupling. We show that the velocity field associated with the rotation of the fluid exhibits diffused vorticity, in contrast to the irrotational behavior char...
1609.04694v2
2016-09-20
Exclusive Weak Radiative Higgs Decays in the Standard Model and Beyond
We perform a detailed study of the exclusive Higgs decays $h\to MZ$ and $h\to MW$, where $M$ is a pseudoscalar or vector meson, using the QCD factorization approach. We allow for the presence of new-physics effects in the form of modified Higgs couplings to gauge bosons and fermions, including the possibility of flavor...
1609.06310v2
2016-09-28
Measuring the trilinear neutral Higgs boson couplings in the MSSM at $e^+ e^-$ colliders
We consider the measurement of the trilinear couplings of the neutral Higgs bosons~($H^0, h^0$) in the minimal supersymmetric standard model~(MSSM) at a high energy $e^+$ $e^-$ linear collider in the light of the discovery of a Higgs boson at the CERN Large Hadron Collider~(LHC). We identify the state observed at the L...
1609.08796v1
2016-09-30
Transition moments between excited electronic states from the Hermitian formulation of the coupled cluster quadratic response function
We introduce a new method for the computation of the transition moments between the excited electronic states based on the expectation value formalism of the coupled cluster theory [B. Jeziorski and R. Moszynski, Int. J. Quant. Chem. 48, 161 (1993)]. The working expressions of the new method solely employ the coupled c...
1609.09769v2
2016-11-02
Topological Quantum Liquids with Long-Range Couplings
Very few topological systems with long-range couplings have been considered so far due to our lack of analytic approaches. Here we extend the Kitaev chain, a 1D quantum liquid, to infinite-range couplings and study its topological properties. We demonstrate that, even though topological phases are intimately linked to ...
1611.00796v2