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Stability of the decagonal quasicrystal in the Lennard-Jones-Gauss system: Although quasicrystals have been studied for 25 years, there are many open questions concerning their stability: What is the role of phason fluctuations? Do quasicrystals transform into periodic crystals at low temperature? If yes, by what mec...
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Study of superfluid $^3$He under nanoscale confinement. A new approach to the investigation of superfluid $^3$He films: We review recent experiments in which superfluid $^3$He has been studied under highly controlled confinement in nanofluidic sample chambers. We discuss the experimental challenges and their resoluti...
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Creating stable molecular condensate using a generalized Raman adiabatic passage scheme: We study the Feshbach resonance assisted stimulated adiabatic passage of an effective coupling field for creating stable molecules from atomic Bose condensate. By exploring the properties of the coherent population trapping state...
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Finite Temperature Dynamics of Spin Solitons with Applications in Thermocouples and Refrigerators: The exploitation of spin Berry phases to generate emergent fields for producing miniaturized and high-quality inductors has enjoyed considerable popularity among proponents of quantum technologies [Nature 586, 202 (2020...
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Superfluid shells for trapped fermions with mass and population imbalance: We map out the phase diagram of strongly interacting fermions in a potential trap with mass and population imbalance between the two spin components. As a unique feature distinctively different from the equal-mass case, we show that the superf...
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Symbiotic Solitons in Heteronuclear Multicomponent Bose-Einstein condensates: We show that bright solitons exist in quasi-one dimensional heteronuclear multicomponent Bose-Einstein condensates with repulsive self-interaction and attractive inter-species interaction. They are remarkably robust to perturbations of init...
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Virial theorems for trapped cold atoms: We present a general virial theorem for quantum particles with arbitrary zero-range or finite-range interactions in an arbitrary external potential. We deduce virial theorems for several situations relevant to trapped cold atoms: zero-range interactions with and without Efimov ef...
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Effect of fluctuations on the superfluid-supersolid phase transition on the lattice: We derive a controlled expansion into mean field plus fluctuations for the extended Bose-Hubbard model, involving interactions with many neighbors on an arbitrary periodic lattice, and study the superfluid-supersolid phase transition...
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Probing the intrinsic state of a one-dimensional quantum well with a photon-assisted tunneling: The photon-assisted tunneling (PAT) through a single wall carbon nanotube quantum well (QW) under influence an external electromagnetic field for probing of the Tomonaga Luttinger liquid (TLL) state is suggested. The eleme...
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Ultracold atoms confined in an optical lattice plus parabolic potential: a closed-form approach: We discuss interacting and non-interacting one dimensional atomic systems trapped in an optical lattice plus a parabolic potential. We show that, in the tight-binding approximation, the non-interacting problem is exactly ...
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Full counting statistics of heteronuclear molecules from Feshbach-assisted photo association: We study the effects of quantum statistics on the counting statistics of ultracold heteronuclear molecules formed by Feshbach-assisted photoassociation [Phys. Rev. Lett. {\bf 93}, 140405 (2004)]. Exploiting the formal simila...
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Electric power transfer in spin pumping experiments: Spin pumping is becoming an established method to generate voltages from magnetic dynamics. The standard detection method of spin pumping is based on open circuit voltage measurement across ferromagnetic (FM) and non-magnetic (NM) bi-layers, where the inverse spin-Ha...
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The absence of fragmentation in Bose-Einstein condensates: A Bose-Einstein condensate produced by a Hamiltonian which is rotationally or translationally symmetric is fragmented as a direct result of these symmetries. A corresponding mean-field unfragmented state, with an identical energy to leading order in the number ...
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Possible experiment for determination of the role of microscopic vortex rings in the λ-transition in He-II: It is suggested that microscopic vortex rings (MVR) play an important role in the \lambda-transition in helium-II and substantially determine the value of T_{\lambda}. For very thin films of He-II, with thickne...
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Phase diagram for a Bose-Einstein condensate moving in an optical lattice: The stability of superfluid currents in a system of ultracold bosons was studied using a moving optical lattice. Superfluid currents in a very weak lattice become unstable when their momentum exceeds 0.5 recoil momentum. Superfluidity vanishes...
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Endurance Write Speed Tradeoffs in Nonvolatile Memories: We derive phenomenological model for endurance-write time switching tradeoff for nonvolatile memories with thermally activated switching mechanisms. The model predicts linear to cubic dependence of endurance on write time for metal oxide memristors and flash memo...
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A Tonks Giradeau Gas in the Presence of a Local Potential: The physics of a Tonks-Giradeau Gas in the presence of a local potential is studied. In order to evaluate the single particle density matrix (SPDM) of the many-body ground state, the Wiger-Jordan transformation is used. The eigenvector with the largest eigenval...
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Topologically trapped vortex molecules in Bose-Einstein condensates: In a numerical experiment based on Gross-Pitaevskii formalism, we demonstrate unique topological quantum coherence in optically trapped Bose-Einstein condensates (BECs). Exploring the fact that vortices in rotating BEC can be pinned by a geometric arr...
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Equation of state of cubic boron nitride at high pressures and temperatures: We report accurate measurements of the equation of state (EOS) of cubic boron nitride by x-ray diffraction up to 160 GPa at 295 K and 80 GPa in the range 500-900 K. Experiments were performed on single-crystals embedded in a quasi-hydrostati...
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The Plastic Flow of Solid 4He through a Porous Membrane: The flow velocity of solid 4He through a porous membrane frozen into a crystal has been measured in the temperature interval 0.1 - 1.8 K. A flat capacitor consisting of a metalized plastic porous membrane and a bulk electrode is applied and the gap in the capacit...
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Dynamics of matter-wave and optical fields in superradiant scattering from Bose-Einstein condensates: We study superradiant scattering off Bose-Einstein condensates by solving the semiclassical Maxwell-Schroedinger equations describing the coupled dynamics of matter-wave and optical fields. Taking the spatial depende...
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Long-range correlation energies and off-diagonal interactions for the $π$ electronic systems: The long-range correlation energies and the off-diagonal interactions are studied and a general formula for correlation energy $E_c$ of the $\pi$ electron systems is given, which is beyond the nearest-neighbor electron-elect...
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Critical temperature of a trapped Bose gas: comparison of theory and experiment: We apply the Projected Gross-Pitaevskii equation (PGPE) formalism to the experimental problem of the shift in critical temperature $T_c$ of a harmonically confined Bose gas as reported in Gerbier \emph{et al.} [Phys. Rev. Lett. \textbf{9...
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Low-energy effective theory of the toric code model in a parallel field: We determine analytically the phase diagram of the toric code model in a parallel magnetic field which displays three distinct regions. Our study relies on two high-order perturbative expansions in the strong- and weak-field limit, as well as a la...
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Estimation of the spatial decoherence time in circular quantum dots: We propose a simple phenomenological model to estimate the spatial decoherence time in quantum dots. The dissipative phase space dynamics is described in terms of the density matrix and the corresponding Wigner function, which are derived from a maste...
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The Linear and Non-linear Magnetic Response of a Tri-Uranium Single Molecule Magnet: We report here low temperature magnetization isotherms for the single molecule magnet, $(UO_2-L)_3$. By analyzing the low temperature magnetization in terms of $M= X_1*B + X_3*B^3$ we extract the linear susceptibility $X_1$ and the l...
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Adiabatic Transport of Bose-Einstein Condensate in Double- and Triple-Well Traps: By using a close similarity between multi-photon and tunneling population transfer schemes, we propose robust adiabatic methods for the transport of Bose-Einstein condensate (BEC) in double- and triple-well traps. The calculations withi...
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Applying matrix product operators to model systems with long-range interactions: An algorithm is presented which computes a translationally invariant matrix product state approximation of the ground state of an infinite 1D system; it does this by embedding sites into an approximation of the infinite ``environment'' o...
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S-mixing and quantum tunneling of the magnetization in molecular nanomagnets: The role of $S$-mixing in the quantum tunneling of the magnetization in nanomagnets has been investigated. We show that the effect on the tunneling frequency is huge and that the discrepancy (more than 3 orders of magnitude in the tunneling...
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Electron sound in metals: This paper is devoted to the investigation of electron sound -- oscillations of the electron distribution function coupled with elastic deformation and propagating with the Fermi velocity. The amplitude-phase relations characterizing the behavior of the electron sound in Ga single crystals are...
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Full transmission through perfect-conductor subwavelength hole arrays: Light transmission through 2D subwavelength hole arrays in perfect-conductor films is shown to be complete (100%) at some resonant wavelengths even for arbitrarily narrow holes. Conversely, the reflection on a 2D planar array of non-absorbing scatte...
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Entanglement and errors in the control of spins by optical coupling: We analyze the optical quantum control of impurity spins in proximity to a quantum dot. A laser pulse creates an exciton in the dot and controls the spins by indirect coupling. We show how to determine the control parameters using as an illustration t...
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Photoinduced vibronic coupling in two-level dissipative systems: Interaction of an electron system with a strong electromagnetic wave leads to rearrangement both the electron and vibrational energy spectra of a dissipative system. For instance, the optically coupled electron levels become split in the conditions of the...
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Continuum Mechanics for Quantum Many-Body Systems: The Linear Response Regime: We derive a closed equation of motion for the current density of an inhomogeneous quantum many-body system under the assumption that the time-dependent wave function can be described as a geometric deformation of the ground-state wave func...
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Evolution of Electronic and Vibrational Polarity of NaF Nanocrystals from Diatomic to Bulk: A Density Functional Study: Density functional theory (DFT) is used to study vibrations, electrical dipole moments, and polarizabilities of NaF clusters. Because of prior experimental and theoretical studies, this is a good mo...
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On non-markovian nature of stock trading: Using a relationship between the moments of the probability distribution of times between the two consecutive trades (intertrade time distribution) and the moments of the distribution of a daily number of trades we show, that the underlying point process generating times of the...
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Manifolds of quasi-constant SOAP and ACSF fingerprints and the resulting failure to machine learn four-body interactions: Atomic fingerprints are commonly used for the characterization of local environments of atoms in machine learning and other contexts. In this work, we study the behavior of two widely used fingerp...
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Possible display of phason mode of electromagnons in TbMnO3: The interaction of light in terahertz frequency region with electromagnons in a sinusoidal incommensurate magnetic state in TbMnO3 is studied. A significant change in the frequency dependence of the dielectric constant e_zz near the temperature of the phase t...
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Dynamical Instability of a Doubly Quantized Vortex in a Bose-Einstein condensate: Doubly quantized vortices were topologically imprinted in $|F=1>$ $^{23}$Na condensates, and their time evolution was observed using a tomographic imaging technique. The decay into two singly quantized vortices was characterized and att...
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Stability and excitations of solitons in 2D Bose-Einstein condensates: The small oscillations of solitons in 2D Bose-Einstein condensates are investigated by solving the Kadomtsev-Petviashvili equation which is valid when the velocity of the soliton approaches the speed of sound. We show that the soliton is stable and ...
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Sandpiles and superconductors: dual variational formulations for critical-state problems: Similar evolutionary variational inequalities appear as convenient formulations for continuous models for sandpile growth, magnetization of type-II superconductors, and evolution of some other dissipative systems characterized b...
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Discontinuities in fourth sound waves in superfluid helium: Formation of fourth-sound shock waves in narrow channels filled with superfluid helium is studied. Physical and mathematical conditions at the surface of discontinuity are established. These conditions differ somewhat from those in case of first- and second-so...
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Inhibition of Transport of a Bose-Einstein Condensate in a Random Potential: We observe the suppression of the 1D transport of an interacting elongated Bose-Einstein condensate in a random potential with a standard deviation small compared to the typical energy per atom, dominated by the interaction energy. Numerical...
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Aging in Citation Networks: In many growing networks, the age of the nodes plays an important role in deciding the attachment probability of the incoming nodes. For example, in a citation network, very old papers are seldom cited while recent papers are usually cited with high frequency. We study actual citation networ...
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Tunneling in a uniform one-dimensional superfluid: emergence of a complex instanton: In a uniform ring-shaped one-dimensional superfluid, quantum fluctuations that unwind the order parameter need to transfer momentum to quasiparticles (phonons). We present a detailed calculation of the leading exponential factor gove...
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Electron guiding through insulating nanocapillaries: We simulate the electron transmission through insulating Mylar (PET) capillaries. We show that the mechanisms underlying the recently discovered electron guiding are fundamentally different from those for ion guiding. Quantum reflection and multiple near-forward scat...
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Special relativity description of the heat propagation in Minkowski spacetime: In this paper we investigate the heat transport induced by continuous laser beams up to an intensity of about 1029 Watt/cm2. We maintain that up to this intensity nonlinear effects are negligible and that the application of the linear hype...
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Rare-earth solid-state qubits: Quantum bits (qubits) are the basic building blocks of any quantum computer. Superconducting qubits have been created with a 'top-down' approach that integrates superconducting devices into macroscopic electrical circuits [1-3], whereas electron-spin qubits have been demonstrated in quant...
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Stability of the decagonal quasicrystal in the Lennard-Jones-Gauss system: Although quasicrystals have been studied for 25 years, there are many open questions concerning their stability: What is the role of phason fluctuations? Do quasicrystals transform into periodic crystals at low temperature? If yes, by what mec...
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Resonantly enhanced tunneling of Bose-Einstein condensates in periodic potentials: We report on measurements of resonantly enhanced tunneling of Bose-Einstein condensates loaded into an optical lattice. By controlling the initial conditions of our system we were able to observe resonant tunneling in the ground and th...
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Laser tweezers for atomic solitons: We describe a controllable and precise laser tweezers for Bose-Einstein condensates of ultracold atomic gases. In our configuration, a laser beam is used to locally modify the sign of the scattering length in the vicinity of a trapped BEC. The induced attractive interactions between ...
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Relaxation and decoherence in a resonantly driven qubit: Relaxation and decoherence of a qubit coupled to environment and driven by a resonant ac field are investigated by analytically solving Bloch equation of the qubit. It is found that the decoherence of a driven qubit can be decomposed into intrinsic and field-depe...
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A Semiclassical Model for Molecular Localization in Ammonia: The pedagogic two stste system of the ammonia molecule is used to illustrate the phenomenon of environment induced molecular localization in pyramidal molecules. A semiclassical model is used to describe a gas of pyramidal molecules interacting via hard ball ...
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Resonant control of spin dynamics in ultracold quantum gases by microwave dressing: We study experimentally interaction-driven spin oscillations in optical lattices in the presence of an off-resonant microwave field. We show that the energy shift induced by this microwave field can be used to control the spin oscilla...
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The role of Helium-3 impurities in the stress induced roughening of superclimbing dislocations in solid Helium-4: We analyze the stress induced and thermally assisted roughening of a forest of superclimbing dislocations in a Peierls potential in the presence of Helium-3 impurities and randomly frozen in static stress...
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Formulas and equations for finding scattering data from the Dirichlet-to-Neumann map with nonzero background potential: For the Schrodinger equation at fixed energy with a potential supported in a bounded domain we give formulas and equations for finding scattering data from the Dirichlet-to-Neumann map with nonzero ...
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Breakdown of Potential Flow to Turbulence around a Sphere Oscillating in Superfluid He-4 above the Critical Velocity: The onset of turbulent flow around an oscillating sphere in superfluid $^4$He is known to occur at a critical velocity $v_c \sim \sqrt{\kappa\omega}$ where $\kappa$ is the circulation quantum and $\om...
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Quantum liquid of repulsively bound pairs of particles in a lattice: Repulsively interacting particles in a periodic potential can form bound composite objects, whose dissociation is suppressed by a band gap. Nearly pure samples of such repulsively bound pairs of cold atoms -- "dimers" -- have recently been prepared by...
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Coherent adiabatic theory of two-electron quantum dot molecules in external spin baths: We derive an accurate molecular orbital based expression for the coherent time evolution of a two-electron wave function in a quantum dot molecule where the electrons interact with each other, with external time dependent electrom...
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The density maximum of He4 at the lambda point modeled by the stochastic quantum hydrodynamic analogy: The lambda point in liquid He4 is a well established phenomenon acknowledged as an example of Bose-Einstain condensation. This is generally accepted, but there are serious discrepancies between the theory and experi...
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Pseudospin excitations in coaxial nanotubes: In a 2DEG confined to two coaxial tubes the `tube degree of freedom' can be described in terms of pseudospin-1/2 dynamics. The presence of tunneling between the two tubes leads to a collective oscillation known as pseudospin resonance. We employ perturbation theory to examin...
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Superfluid hydrodynamics in fractal dimension space: The complex behavior of liquid ${}^4$He and liquid ${}^3$He in nanoporous media is determined by influence of randomly distributed geometrical confinement as well as by significant contribution from the atoms near walls. In the present paper fractional Schrodinger eq...
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The scaling of the density of states in systems with resonance states: Resonance states of a two-electron quantum dot are studied using a variational expansion with both real basis-set functions and complex scaling methods. We present numerical evidence about the critical behavior of the density of states in the region...
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Luttinger parameter of quasi-one-dimensional para-H2: We have studied the ground-state properties of para-hydrogen in one dimension and in quasi-one-dimensional configurations using the path integral ground state Monte Carlo method. This method produces zero-temperature exact results for a given interaction and geometr...
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On the Laser Stimulation of Low-Energy Nuclear Reactions in Deuterated Palladium: Models to account for the observed experimental results for low-energy nuclear reactions in palladium-deuteride systems are presented along with calculated results. The crucial idea is a mechanism of improved probability for the needed ...
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Coherent optical control of spin-spin interaction in doped semiconductors: We provide a theory of laser-induced interaction between spins localized by impurity centers in a semiconductor host. By solving exactly the problem of two localized spins interacting with one itinerant exciton, an analytical expression for th...
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Detection of vortex coherent structures in superfluid turbulence: Filamentary regions of high vorticity irregularly form and disappear in the turbulent flows of classical fluids. We report an experimental comparative study of these so-called " coherent structures " in a classical versus quantum fluid, using liquid heli...
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Correlation functions of cold bosons in an optical lattice: We investigate the experiment of collapses and revivals of matter wave field in more detail. To this end we calculate the lowest-order correlation functions of the Bose field. We compare predictions of the total Fock state with the commonly used coherent state...
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Li Doping Effect on Properties and Phase Transfomations of Knbo3: Dielectric permittivity and infrared reflectivity spectra of Li doped KNbO3 single crystals have been studied for the first time for K1-xLixNbO3 (KLN) with x = 0.015, 0.02, 0.065. It was found that like in KTaO3, Li admixture results in appearance of die...
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Vortices in Bose-Einstein Condensates: Some Recent Developments: In this brief review we summarize a number of recent developments in the study of vortices in Bose-Einstein condensates, a topic of considerable theoretical and experimental interest in the past few years. We examine the generation of vortices by means of...
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Photon recycling in Fabry-Perot micro-cavities based on Si$_3$N$_4$ waveguides: We present a numerical analysis and preliminary experimental results on one-dimensional Fabry-Perot micro-cavities in Si$_3$N$_4$ waveguides. The Fabry-Perot micro-cavities are formed by two distributed Bragg reflectors separated by a str...
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Theoretical Studies on the Scanning Tunneling Microscope: The thesis explores calculating tunneling current densities between planar conducting electrodes in an STM. It considers factors like bias voltages and the separation between electrodes, using Fermi energy and work functions. Pauli blocking effects on forward an...
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Large scale numerical simulations of "ultrametric" long-range depinning: The depinning of an elastic line interacting with a quenched disorder is studied for long range interactions, applicable to crack propagation or wetting. An ultrametric distance is introduced instead of the Euclidean distance, allowing for a drast...
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Semiclassical and quantum polarons in crystaline acetanilide: Crystalline acetanilide is a an organic solid with peptide bond structure similar to that of proteins. Two states appear in the amide I spectral region having drastically different properties: one is strongly temperature dependent and disappears at high temp...
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Bose-Einstein condensates of polar molecules: anisotropic interactions = anisotropic mass: So far the theory of Bose-Einstein condensates (BEC) of polar molecules was based on an ad hoc generalization of equations for spherical atoms. Here I adopt a rigorous pseudo-potential approach to low-energy dipolar interaction...
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Bright solitary waves of atomic Bose-Einstein condensates under rotation: We analyse the rotation of bright solitary waves formed of atomic Bose-Einstein condensates with attractive atomic interactions. By employing a variational technique and assuming an irrotational quadrupolar flow field, we map out the variational ...
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Reaction Enhanced Diffusion in Spherical Membranes: The reversible reactions like A+B <-> C in the many-component diffusive system affect the diffusive properties of the constituents. The effective conjugation of irreversible processes of different dimensionality takes place due to the stationarity in the system and ca...
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Levels of self-consistency in the GW approximation: We perform $GW$ calculations on atoms and diatomic molecules at different levels of self-consistency and investigate the effects of self-consistency on total energies, ionization potentials and on particle number conservation. We further propose a partially self-consi...
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Magnetization dynamics in dysprosium orthoferrites via inverse Faraday effect: The ultrafast non-thermal control of magnetization has recently become feasible in canted antiferromagnets through photomagnetic instantaneous pulses [A.V. Kimel {\it et al.}, Nature {\bf 435}, 655 (2005)]. In this experiment circularly po...
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Financial heat machine: We consider dynamics of financial markets as dynamics of expectations and discuss such a dynamics from the point of view of phenomenological thermodynamics. We describe a financial Carnot cycle and the financial analogue of a heat machine. We see, that while in physics a perpetuum mobile is abso...
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Ultrasensitive nanoelectromechanical mass detection: We describe the application of nanoelectromechanical systems (NEMS) to ultrasensitive mass detection. In these experiments, a modulated flux of atoms was adsorbed upon the surface of a 32.8 MHz NEMS resonator within an ultrahigh vacuum environment. The mass-induced r...
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Topological Constraints on the Charge Distributions for the Thomson Problem: The method of Morse theory is used to analyze the distributions of unit charges interacting through a repulsive force and constrained to move on the surface of a sphere -- the Thomson problem. We find that, due to topological reasons, the sy...
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Comment on the paper "Quasi-particle approach for lattice Hamiltonians with large coordination numbers" by P. Navez, F. Queisser and R. Schützhold - J. Phys. A: Math. Theor. 47 225004 (2014): This comment regards a central aspect of the referred-to paper, the issue of convergence of the large coordination-number ex...
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A Guided Walk Down Wall Street: an Introduction to Econophysics: This article contains the lecture notes for the short course ``Introduction to Econophysics,'' delivered at the II Brazilian School on Statistical Mechanics, held in Sao Carlos, Brazil, in February 2004. The main goal of the present notes is twofold: i) t...
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Observation of Majorana Quasiparticles Surface States in Superfluid ${^3}$He-B by Heat Capacity Measurements: We report about direct measurements of heat capacity of Majorana quasiparticles in superfluid ${^3}$He-B which appear near the surface of the experimental bolometer on the coherence length ${\xi}$. Two bolome...
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Stability of low-dimensional multicomponent Bose gases: I show that in low dimensions the interactions in dilute Bose mixtures are strongly renormalized, which leads to a considerable change of stability conditions compared to the mean-field results valid in the high-density regime. Estimates are given for the two-comp...
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Non-local density correlations as signal of Hawking radiation in BEC acoustic black holes: We have used the analogy between gravitational systems and non-homogeneous fluid flows to calculate the density-density correlation function of an atomic Bose-Einstein condensate in the presence of an acoustic black hole. The e...
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Dynamic localization in an effective tight binding Hamiltonian model with a rapidly oscillating homogeneous electric field on a lattice: By the Magnus-Floquet approach we calculate the effective Hamiltonian for a charged particle on the lattice subject to a homogeneous high frequency oscillating electric field. The o...
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Critical Velocities for Roton and Super-Flow Quantum Turbulence in Liquid $^4$He: Two different types of transitions of the superfluid $^4$He to quantum turbulence regimes are studied for $1{\rm D}$ geometry in the case when the influence of the normal fluid on superfluid flow is suppressed. It is shown that the roto...
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Hard-core bosons on optical superlattices: Dynamics and relaxation in the superfluid and insulating regimes: We study the ground-state properties and nonequilibrium dynamics of hard-core bosons confined in one-dimensional lattices in the presence of an additional periodic potential (superlattice) and a harmonic trap....
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Modification to the pre-factor of the semiclassical propagator: We modify the pre-factor of the semiclassical propagator to improve its efficiency in practical implementations. The new pre-factor represents the smooth portion of an orbit's contribution, and leads to fast convergence in numerical calculations. As an ill...
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Giant magnetic anisotropy of the bulk antiferromagnets IrMn and IrMn3: Theoretical predictions of the magnetic anisotropy of antiferromagnetic materials are demanding due to a lack of experimental techniques which are capable of a direct measurement of this quantity. At the same time it is highly significant due to the...
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Electronic structure via potential functional approximations: The universal functional of Hohenberg-Kohn is given as a coupling-constant integral over the density as a functional of the potential. Conditions are derived under which potential-functional approximations are variational. Construction via this method and im...
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Experimental realization of BCS-BEC crossover physics with a Fermi gas of atoms: This thesis presents experiments probing physics in the crossover between Bose-Einstein condensation (BEC) and BCS superconductivity using an ultracold gas of atomic fermions. Scattering resonances in these ultracold gases (known as Fesh...
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Commensurability and hysteretic evolution of vortex configurations in rotating optical lattices: We present a theoretical study of vortices within a harmonically trapped Bose-Einstein condensate in a rotating optical lattice. Due to the competition between vortex-vortex interactions and pinning to the optical lattice...
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Diffusion and localization for the Chirikov typical map: We consider the classical and quantum properties of the "Chirikov typical map", proposed by Boris Chirikov in 1969. This map is obtained from the well known Chirikov standard map by introducing a finite number $T$ of random phase shift angles. These angles induce...
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Trapped Fermions across a Feshbach resonance with population imbalance: We investigate the phase separation of resonantly interacting fermions in a trap with imbalanced spin populations, both at zero and at finite temperatures. We directly minimize the thermodynamical potential under the local density approximation ins...
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On the free rotation of a molecule embedded in helium-4 clusters: The fact, that $^4$He atoms on different concentric circular paths around the axis of a quantum vortex move with identically equal angular momentum, which represents an important aspect of superfluidity of He-II, has been used to discover a model which c...
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Laser Pulse Amplification with Bose-Einstein Condensates: This paper has been withdrawn by the author.
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Microstructure of He II in the presence of boundaries: We have studied the microstructure of a system of interacting Bose particles under zero boundary conditions and have found two possible orderings. One ordering is traditional and is characterized by the Bogolyubov dispersion law E^2 = (h^2 k^2/2m)^{2} + qn\nu(k)[h^...
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