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Feshbach resonances of harmonically trapped atoms: Employing a short-range two-channel description we derive an analytic model of atoms in isotropic and anisotropic harmonic traps at a Feshbach resonance. On this basis we obtain a new parameterization of the energy-dependent scattering length which differs from the one...
cond-mat_quant-gas
Curving the space by non-Hermiticity: Quantum systems are often classified into Hermitian and non-Hermitian ones. Extraordinary non-Hermitian phenomena, ranging from the non-Hermitian skin effect to the supersensitivity to boundary conditions, have been widely explored. Whereas these intriguing phenomena have been cons...
cond-mat_quant-gas
Two-dimensional dynamics of expansion of a degenerate Bose gas: Expansion of a degenerate Bose gas released from a pancakelike trap is numerically simulated under the assumption of separation of the motion in the plane of the loose initial trapping and the motion in the direction of the initial tight trapping. The init...
cond-mat_quant-gas
Spin 1 microcondensate in a magnetic field: semiclassics and exact solution: We study a spin 1 Bose condensate small enough to be treated as a single magnetic `domain': a system that we term a microcondensate. Because all particles occupy a single spatial mode, this quantum many body system has a well defined classic...
cond-mat_quant-gas
Multi-wavelength holography with a single Spatial Light Modulator for ultracold atom experiments: We demonstrate a method to create arbitrary intensity distributions of multiple wavelengths of light, which can be useful for ultracold atom experiments, by using regional phase-calculation algorithms to find a single ho...
cond-mat_quant-gas
Thermalized Abrikosov lattices from decaying turbulence in rotating BECs: We study the long-time decay of rotating turbulence in Bose-Einstein condensates (BECs). We consider the Gross-Pitaevskii equation in a rotating frame of reference, and review different formulations for the Hamiltonian of a rotating BEC. We discu...
cond-mat_quant-gas
Ultracold Atomic Gases: Novel States of Matter: Article to appear in the Encyclopedia of Complexity and Systems Science, Dr. R. A. Meyers (Ed.) (Springer Heidelberg, 2009).
cond-mat_quant-gas
Faraday patterns in spin-orbit coupled Bose-Einstein condensates: We study the Faraday patterns generated by spin-orbit-coupling induced parametric resonance in a spinor Bose-Einstein condensate with repulsive interaction. The collective elementary excitations of the Bose-Einstein condensate, including density waves an...
cond-mat_quant-gas
Entanglement prethermalization: Locally thermal but non-locally non-thermal states in a one-dimensional Bose gas: A well-isolated system often shows relaxation to a quasi-stationary state before reaching thermal equilibrium. Such a prethermalization has attracted considerable interest recently in association with clo...
cond-mat_quant-gas
Persistent oscillations of the order parameter and interaction quench phase diagram for a confined Bardeen-Cooper-Schrieffer Fermi gas: We present a numerical study of the interaction quench dynamics in a superfluid ultracold Fermi gas confined in a three-dimensional cigar-shaped harmonic trap. In the present paper w...
cond-mat_quant-gas
Stability of Excited Dressed States with Spin-Orbit Coupling: We study the decay behaviors of ultracold atoms in metastable states with spin-orbit coupling (SOC), and demonstrate that there are two SOC-induced decay mechanisms. One arises from the trapping potential and the other is due to interatomic collision. We pre...
cond-mat_quant-gas
Quantum theory of bright matter wave solitons in harmonic confinement: This paper investigates bright quantum-matter-wave solitons beyond the Gross-Pitaevskii equation (GPE). As proposals for interferometry and creating nonlocal quantum superpositions have been formed, it has become necessary to investigate effects not...
cond-mat_quant-gas
Exact solutions to the four Goldstone modes around a dark soliton of the nonlinear Schroedinger equation: This article is concerned with the linearisation around a dark soliton solution of the nonlinear Schr\"odinger equation. Crucially, we present analytic expressions for the four linearly-independent zero eigenvalu...
cond-mat_quant-gas
Interaction induced dynamical $\mathcal{PT}$ symmetry breaking in dissipative Fermi-Hubbard models: We investigate the dynamical properties of one-dimensional dissipative Fermi-Hubbard models, which are described by the Lindblad master equations with site-dependent jump operators. The corresponding non-Hermitian effe...
cond-mat_quant-gas
Coherent Interaction of a Single Fermion with a Small Bosonic Field: We have experimentally studied few-body impurity systems consisting of a single fermionic atom and a small bosonic field on the sites of an optical lattice. Quantum phase revival spectroscopy has allowed us to accurately measure the absolute strength ...
cond-mat_quant-gas
Asymmetric Particle Transport and Light-Cone Dynamics Induced by Anyonic Statistics: We study the non-equilibrium dynamics of Abelian anyons in a one-dimensional system. We find that the interplay of anyonic statistics and interactions gives rise to spatially asymmetric particle transport together with a novel dynami...
cond-mat_quant-gas
Spin and mass currents near a moving magnetic obstacle in a two-component Bose-Einstein condensate: We study the spatial distributions of the spin and mass currents generated by a moving Gaussian magnetic obstacle in a symmetric, two-component Bose-Einstein condensate in two dimensions. We analytically describe the c...
cond-mat_quant-gas
Many-body approach to low-lying collective excitations in a BEC approaching collapse: An approximate many-body theory incorporating two-body correlations has been employed to calculate low-lying collective multipole frequencies in a Bose-Einstein condensate containing $A$ bosons, for different values of the interacti...
cond-mat_quant-gas
Optical lattice for tripod-like atomic level structure: Standard optical potentials use off-resonant laser standing wave induced AC-Stark shift. In a recent development [Phys. Rev. Lett. {\bf 117}, 233001 (2016)] a three-level scheme in $\Lambda$ configuration coupled coherently by resonant laser fields was introduced ...
cond-mat_quant-gas
Quantum-granularity effect in the formation of supermixed solitons in ring lattices: We investigate a notable class of states peculiar to a bosonic binary mixture featuring repulsive intraspecies and attractive interspecies couplings. We evidence that, for small values of the hopping amplitudes, one can access partic...
cond-mat_quant-gas
Quantum-torque-induced breaking of magnetic interfaces in ultracold gases: A rich variety of physical effects in spin dynamics arises at the interface between different magnetic materials. Engineered systems with interlaced magnetic structures have been used to implement spin transistors, memories and other spintroni...
cond-mat_quant-gas
Tunable Wigner States with Dipolar Atoms and Molecules: We study the few-body physics of trapped atoms or molecules with electric or magnetic dipole moments aligned by an external field. Using exact numerical diagonalization appropriate for the strongly correlated regime, as well as a classical analysis, we show how Wi...
cond-mat_quant-gas
Dissipation-induced dynamical phase transition in postselected quantum trajectories: It is known that effects of dissipation or measurement backreaction in postselected quantum trajectories are described by non-Hermitian Hamiltonian, but their consequences in real-time dynamics of many-body systems are yet to be eluc...
cond-mat_quant-gas
Feynman path-integral treatment of the Bose polaron beyond the Fröhlich model: An impurity immersed in a Bose-Einstein condensate is no longer accurately described by the Fr\"ohlich Hamiltonian as the coupling between the impurity and the boson bath gets stronger. We study the dominant effects of the two-phonon terms...
cond-mat_quant-gas
Measuring molecular electric dipoles using trapped atomic ions and ultrafast laser pulses: We study a hybrid quantum system composed of an ion and an electric dipole. We show how a trapped ion can be used to measure the small electric field generated by a classical dipole. We discuss the application of this scheme to...
cond-mat_quant-gas
Finite-size effects on the Bose-Einstein condensation critical temperature in a harmonic trap: We obtain second and higher order corrections to the shift of the Bose-Einstein critical temperature due to finite-size effects. The confinement is that of a harmonic trap with general anisotropy. Numerical work shows the h...
cond-mat_quant-gas
Controlling particle current in a many-body quantum system by external driving: We propose a method to control the particle current of a one-dimensional quantum system by resonating two many-body states through an external driving field. We consider the Bose-Hubbard and spinless Fermi-Hubbard models with the Peierls ...
cond-mat_quant-gas
Few-to-many vortex states of density-angular-momentum coupled Bose-Einstein condensates: Motivated by recent experiments, we theoretically study a gas of atomic bosons confined in an elliptical harmonic trap; forming a quasi-two-dimensional atomic Bose-Einstein condensate subject to a density-dependent gauge potentia...
cond-mat_quant-gas
Orbital superfluidity in the $P$-band of a bipartite optical square lattice: The successful emulation of the Hubbard model in optical lattices has stimulated world wide efforts to extend their scope to also capture more complex, incompletely understood scenarios of many-body physics. Unfortunately, for bosons, Feynma...
cond-mat_quant-gas
Buckling transitions and clock order of two-dimensional Coulomb crystals: Crystals of repulsively interacting ions in planar traps form hexagonal lattices, which undergo a buckling instability towards a multi-layer structure as the transverse trap frequency is reduced. Numerical and experimental results indicate that t...
cond-mat_quant-gas
Spin-orbit coupling in the presence of strong atomic correlations: We explore the influence of contact interactions on a synthetically spin-orbit coupled system of two ultracold trapped atoms. Even though the system we consider is bosonic, we show that a regime exists in which the competition between the contact and sp...
cond-mat_quant-gas
Generalized Hydrodynamics in the 1D Bose gas: theory and experiments: We review the recent theoretical and experimental progress regarding the Generalized Hydrodynamics (GHD) behavior of the one-dimensional Bose gas with contact repulsive interactions, also known as the Lieb-Liniger gas. In the first section, we review...
cond-mat_quant-gas
Multiorder topological superfluid phase transitions in a two-dimensional optical superlattice: Higher-order topological superfluids have gapped bulk and symmetry-protected Majorana zero modes with various localizations. Motivated by recent advances, we present a proposal for synthesizing multi-order topological super...
cond-mat_quant-gas
Dipolar fermions in a multilayer geometry: We investigate the behavior of identical dipolar fermions with aligned dipole moments in two-dimensional multilayers at zero temperature. We consider density instabilities that are driven by the attractive part of the dipolar interaction and, for the case of bilayers, we eluci...
cond-mat_quant-gas
Flowing bosonization in the nonperturbative functional renormalization-group approach: Bosonization allows one to describe the low-energy physics of one-dimensional quantum fluids within a bosonic effective field theory formulated in terms of two fields: the "density" field $\varphi$ and its conjugate partner, the ph...
cond-mat_quant-gas
Emergent patterns in a spin-orbit coupled spin-2 Bose-Einstein condensate: The ground-state phases of a spin-orbit (SO) coupled atomic spin-2 Bose-Einstein condensate (BEC) are studied. Interesting density patterns spontaneously formed are widespread due to the competition between SO coupling and spin-dependent inter...
cond-mat_quant-gas
Coherent phase slips in coupled matter-wave circuits: Quantum Phase slips are dual process of particle tunneling in coherent networks. Besides to be of central interest for condensed matter physics, quantum phase slips are resources that are sought to be manipulated in quantum circuits. Here, we devise a specific matte...
cond-mat_quant-gas
BCS-BEC crossover at finite temperature in spin-orbit coupled Fermi gases: By adopting a $T$-matrix-based method within the $G_0G$ approximation for the pair susceptibility, we study the effects of the pairing fluctuation on the three-dimensional spin-orbit coupled Fermi gases at finite temperature. The critical temp...
cond-mat_quant-gas
Superdiffusive nonequilibrium motion of an impurity in a Fermi sea: We treat the nonequilibrium motion of a single impurity atom in a low-temperature single-species Fermi sea, interacting via a contact interaction. In the nonequilibrium regime, the impurity does a superdiffusive geometric random walk where the typical ...
cond-mat_quant-gas
Creating quantum many-body scars through topological pumping of a 1D dipolar gas: Quantum many-body scars, long-lived excited states of correlated quantum chaotic systems that evade thermalization, are of great fundamental and technological interest. We create novel scar states in a bosonic 1D quantum gas of dysprosi...
cond-mat_quant-gas
Multi-particle composites in density-imbalanced quantum fluids: We consider two-component one-dimensional quantum gases with density imbalance. While generically such fluids are two-component Luttinger liquids, we show that if the ratio of the densities is a rational number, p/q, and mass asymmetry between components i...
cond-mat_quant-gas
Flux enhanced localization and reentrant delocalization in the quantum walk of interacting bosons on two-leg ladder: We study the quantum walk of two bosons possessing onsite repulsive interaction on a two-leg ladder and show that the presence of uniform flux piercing through the plaquettes of the ladder favors the l...
cond-mat_quant-gas
Dynamical Equilibration of Topological Properties: We study the dynamical process of equilibration of topological properties in quantum many-body systems undergoing a parameter quench between two topologically inequivalent Hamiltonians. This scenario is motivated by recent experiments on ultracold atomic gases, where a...
cond-mat_quant-gas
Controlling Dipolar Exchange Interactions in a Dense 3D Array of Large Spin Fermions: Dipolar interactions are ubiquitous in nature and rule the behavior of a broad range of systems spanning from energy transfer in biological systems to quantum magnetism. Here, we study magnetization-conserving dipolar induced spin-e...
cond-mat_quant-gas
How is the density of quasi-two-dimensional uniform dipolar quantum Bose gases affected by trap imperfections?: We theoretically investigate the impact of weak perturbations of a flat potential on the density of a quasi-two-dimensional dipolar Bose gas. We use a mean-field perturbative treatment of the potential defe...
cond-mat_quant-gas
Spin conductivity spectrum and spin superfluidity in a binary Bose mixture: We investigate the spectrum of spin conductivity for a miscible two-component Bose-Einstein condensate (BEC) that exhibits spin superfluidity. By using the Bogoliubov theory, the regular part being the spin conductivity at finite ac frequency...
cond-mat_quant-gas
Singular mean-field states: A brief review of recent results: This article provides a focused review of recent findings which demonstrate, in some cases quite counter-intuitively, the existence of bound states with a singularity of the density pattern at the center, while the states are physically meaningful because th...
cond-mat_quant-gas
Dynamics of spatial coherence and momentum distribution of polaritons in a semiconductor microcavity under conditions of Bose-Einstein condensation: The dynamics of spatial coherence and momentum distribution of polaritons in the regime of Bose-Einstein condensation are investigated in a GaAs microcavity with embedde...
cond-mat_quant-gas
Quantum information theoretic measures to distinguish fermionized bosons from non-interacting fermions: We study the dynamical fermionization of strongly interacting one-dimensional bosons in Tonks-Girardeau limit by solving the time dependent many-boson Schr\"odinger equation numerically exactly. We establish that t...
cond-mat_quant-gas
Dynamics of exciton-polaritons in a Josephson double dimer: We study the dynamics of exciton-polaritons in a double-well configuration. The system consists of two weakly coupled Bose-Josephson junctions, each corresponding to a different circular polarization of the polaritons, forming a {\it Josephson double dimer}. W...
cond-mat_quant-gas
Evidence of a liquid phase in interacting Bosons at intermediate densities: In this paper, we present evidence for a liquid-like phase in systems of many interacting Bosons at intermediate densities. The interacting Bose gas has been studied extensively in the low and high density regimes, in which interactions do no...
cond-mat_quant-gas
Bidirectional dynamic scaling in an isolated Bose gas far from equilibrium: Understanding and classifying nonequilibrium many-body phenomena, analogous to the classification of equilibrium states of matter into universality classes, is an outstanding problem in physics. Any many-body system, from stellar matter to fi...
cond-mat_quant-gas
Rotational pendulum dynamics of a vortex molecule in a channel geometry: A vortex molecule is a topological excitation in two coherently coupled superfluids consisting of a vortex in each superfluid connected by a domain wall of the relative phase, also known as a Josephson vortex. We investigate the dynamics of this e...
cond-mat_quant-gas
Bose-Einstein Condensation of 84-Sr: We report Bose-Einstein condensation of 84-Sr in an optical dipole trap. Efficient laser cooling on the narrow intercombination line and an ideal s-wave scattering length allow creation of large condensates (N0 ~ 3x10^5) even though the natural abundance of this isotope is only 0.6%...
cond-mat_quant-gas
Dynamic Structure Factor of Normal Fermi Gas from Collisionless to Hydrodynamic Regime: The dynamic structure factor of a normal Fermi gas is investigated by using the moment method for the Boltzmann equation. We determine the spectral function at finite temperatures over the full range of crossover from the collisio...
cond-mat_quant-gas
Small two-component Fermi gases in a cubic box with periodic boundary conditions: The properties of two-component Fermi gases become universal if the interspecies s-wave scattering length $a_s$ and the average interparticle spacing are much larger than the range of the underlying two-body potential. Using an explicit...
cond-mat_quant-gas
Driven-dissipative many-body pairing states for cold fermionic atoms in an optical lattice: We discuss the preparation of many-body states of cold fermionic atoms in an optical lattice via controlled dissipative processes induced by coupling the system to a reservoir. Based on a mechanism combining Pauli blocking and...
cond-mat_quant-gas
AtomECS: Simulate laser cooling and magneto-optical traps: AtomECS is a software package that efficiently simulates the motion of neutral atoms experiencing forces exerted by laser radiation, such as in magneto-optical traps and Zeeman slowers. The program is implemented using the Entity-Component-System pattern, which...
cond-mat_quant-gas
Localization in spin chains with facilitation constraints and disordered interactions: Quantum many-body systems with kinetic constraints exhibit intriguing relaxation dynamics. Recent experimental progress in the field of cold atomic gases offers a handle for probing collective behavior of such systems, in particula...
cond-mat_quant-gas
Grüneisen Parameter for Gases: The Gr\"uneisen ratio ($\Gamma$), i.e.\,the ratio of the linear thermal expansivity to the specific heat at constant pressure, quantifies the degree of anharmonicity of the potential governing the physical properties of a system. While $\Gamma$ has been intensively explored in solid state...
cond-mat_quant-gas
Signatures of Fractional Exclusion Statistics in the Spectroscopy of Quantum Hall Droplets: We show how spectroscopic experiments on a small Laughlin droplet of rotating bosons can directly demonstrate Haldane fractional exclusion statistics of quasihole excitations. The characteristic signatures appear in the single...
cond-mat_quant-gas
Rapidity distribution within the defocusing non-linear Schrödinger equation model: We consider the classical field integrable system whose evolution equation is the nonlinear Schr\"odinger equation with defocusing non-linearities, which is the classical limit of the quantum Lieb-Liniger model. We propose a simple der...
cond-mat_quant-gas
Pairing and the spin susceptibility of the polarized unitary Fermi gas in the normal phase: We theoretically study the pairing behavior of the unitary Fermi gas in the normal phase. Our analysis is based on the static spin susceptibility, which characterizes the response to an external magnetic field. We obtain this ...
cond-mat_quant-gas
Non-perturbative method to compute thermal correlations in one-dimensional systems: A brief overview: We develop a highly efficient method to numerically simulate thermal fluctuations and correlations in non-relativistic continuous bosonic one-dimensional systems. We start by noticing the equivalence of their descrip...
cond-mat_quant-gas
Miscibility-Immiscibility transition of strongly interacting bosonic mixtures in optical lattices: Interaction plays key role in the mixing properties of a multi-component system. The miscibility-immiscibility transition (MIT) in a weakly interacting mixture of Bose gases is predominantly determined by the strengths ...
cond-mat_quant-gas
Adiabatic spin cooling using high-spin Fermi gases: Spatial entropy redistribution plays a key role in adiabatic cooling of ultra-cold lattice gases. We show that high-spin fermions with a spatially variable quadratic Zeeman coupling may allow for the creation of an inner spin-1/2 core surrounded by high-spin wings. Th...
cond-mat_quant-gas
Two-Stage Melting in Systems of Strongly Interacting Rydberg Atoms: We analyze the ground state properties of a one-dimensional cold atomic system in a lattice, where Rydberg excitations are created by an external laser drive. In the classical limit, the ground state is characterized by a complete devil's staircase for...
cond-mat_quant-gas
Probing quantum transport by engineering correlations in a speckle potential: We develop a procedure to modify the correlations of a speckle potential. This procedure, that is suitable for spatial light modulator devices, allows one to increase the localization efficiency of the speckle in a narrow energy region whos...
cond-mat_quant-gas
Vortex gyroscope imaging of planar superfluids: We propose a robust imaging technique that makes it possible to distinguish vortices from antivortices in quasi-two-dimensional Bose--Einstein condensates from a single image of the density of the atoms. Tilting the planar condensate prior to standard absorption imaging e...
cond-mat_quant-gas
Quantum interferometry at zero and finite temperature with two-mode bosonic Josephson junctions: We analyze phase interferometry realized with a bosonic Josephson junction made of trapped dilute and ultracold atoms. By using a suitable phase sensitivity indicator we study the zero temperature junction states useful t...
cond-mat_quant-gas
Topological semimetal in a fermionic optical lattice: Optical lattices play a versatile role in advancing our understanding of correlated quantum matter. The recent implementation of orbital degrees of freedom in chequerboard and hexagonal optical lattices opens up a new thrust towards discovering novel quantum states ...
cond-mat_quant-gas
Resonant dipolar collisions of ultracold molecules induced by microwave dressing: We demonstrate microwave dressing on ultracold, fermionic ${}^{23}$Na${}^{40}$K ground-state molecules and observe resonant dipolar collisions with cross sections exceeding three times the $s$-wave unitarity limit. The origin of these c...
cond-mat_quant-gas
Effect of anisotropic spin-orbit coupling on condensation and superfluidity of a two dimensional Fermi gases: We investigated the ground state properties of a two dimensional Fermi superfluid with an anisotropic spin-orbit coupling (SOC) using path-integral field theoretical method. Within the framework of mean-field...
cond-mat_quant-gas
Imaginary Potential Induced Quantum Coherence for Bose-Einstein Condensates: The role of complex potentials in single-body Schr\H{o}dinger equation has been studied intensively. We study the quantum coherence for degenerate Bose gases in complex potentials, when the exchange symmetry of identical bosons is considered...
cond-mat_quant-gas
Two-body momentum correlations in a weakly interacting one-dimensional Bose gas: We analyze the two-body momentum correlation function for a uniform weakly interacting one-dimensional Bose gas. We show that the strong positive correlation between opposite momenta, expected in a Bose-Einstein condensate with a true lo...
cond-mat_quant-gas
Chiral confinement in quasirelativistic Bose-Einstein condensates: In the presence of a laser-induced spin-orbit coupling an interacting ultra cold spinor Bose-Einstein condensate may acquire a quasi-relativistic character described by a non-linear Dirac-like equation. We show that as a result of the spin-orbit couplin...
cond-mat_quant-gas
Superfluid to Mott insulator transition in the one-dimensional Bose-Hubbard model for arbitrary integer filling factors: We study the quantum phase transition between the superfluid and the Mott insulator in the one-dimensional (1D) Bose-Hubbard model. Using the time-evolving block decimation method, we numerically c...
cond-mat_quant-gas
The spin evolution of spin-3 $^{52}$Cr Bose-Einstein condensate: The spin evolution of a Bose-Einstein condensate starting from a mixture of two or three groups of $^{52}$Cr (spin-3) atoms in an optical trap has been studied theoretically. The initial state is so chosen that the system does not distinguish up and down....
cond-mat_quant-gas
Dynamics of first-order quantum phase transitions in extended Bose-Hubbard model: From density wave to superfluid and vice-versa: In this paper, we study the nonequilibrium dynamics of the Bose-Hubbard model with the nearest-neighbor repulsion by using time-dependent Gutzwiller (GW) methods. In particular, we vary th...
cond-mat_quant-gas
Many-body exceptional points in colliding condensates: Exceptional points describe the coalescence of the eigenmodes of a non-Hermitian matrix. When an exceptional point occurs in the unitary evolution of a many-body system, it generically leads to a dynamical instability with a finite wavevector [N. Bernier \etal, Phy...
cond-mat_quant-gas
Three Identical Fermions with Resonant p-wave Interactions in Two Dimensions: A new kind of "super-Efimov" states of binding energies scaling as $\ln|E_n|\sim-e^{3n\pi/4}$ were predicted by a field theory calculation for three fermions with resonant $p$-wave interactions in two dimensions [Phys. Rev. Lett. \textbf{11...
cond-mat_quant-gas
Relation between the noise correlations and the spin structure factor for Mott-insulating states in SU$(N)$ Hubbard models: It is well established that the noise correlations measured by time-of-flight imaging in cold-atom experiments, which correspond to the density-density correlations in the momentum space of trap...
cond-mat_quant-gas
Thermodynamics of a spin-1 Bose gas with fixed magnetization: We investigate the thermodynamics of a spin-1 Bose gas with fixed magnetization including the quadratic Zeeman energy shift. Our calculations are based on the grand canonical description for the ideal gas and the classical fields approximation for atoms with...
cond-mat_quant-gas
Dynamical Cluster Quantum Monte Carlo Study of the Single Particle Spectra of Strongly Interacting Fermion Gases: We study the single-particle spectral function of resonantly-interacting fermions in the unitary regime, as described by the three-dimensional attractive Hubbard model in the dilute limit. Our approach, b...
cond-mat_quant-gas
Pseudopotential for the 2D contact interaction: We propose a smooth pseudopotential for the contact interaction acting between ultracold atoms confined to two dimensions. The pseudopotential reproduces the scattering properties of the repulsive contact interaction up to 200 times more accurately than a hard disk potent...
cond-mat_quant-gas
Particle Fluctuations in Mesoscopic Bose Systems: Particle fluctuations in mesoscopic Bose systems of arbitrary spatial dimensionality are considered. Both ideal Bose gases and interacting Bose systems are studied in the regions above the Bose-Einstein condensation temperature $T_c$ as well as below this temperature. T...
cond-mat_quant-gas
How creating one additional well can generate Bose-Einstein condensation: The realization of Bose-Einstein condensation in ultracold trapped gases has led to a revival of interest in that fascinating quantum phenomenon. This experimental achievement necessitated both extremely low temperatures and sufficiently weak int...
cond-mat_quant-gas
Critical velocity, vortex shedding and drag in a unitary Fermi superfluid: We study the real-time motion of a microscopic object in a cold Fermi gas at unitary conditions by using an extended Thomas-Fermi density functional approach. We find that spontaneous creation of singly quantized vortex-antivortex pairs occurs...
cond-mat_quant-gas
Direct Observation of Fragmentation in a Disordered, Strongly Interacting Fermi Gas: Describing the behaviour of strongly interacting particles in the presence of disorder is among the most challenging problems in quantum many-body physics. The controlled setting of cold atom experiments provides a new avenue to addr...
cond-mat_quant-gas
Correlated quantum dynamics of graphene: Phase-space representations are a family of methods for dynamics of both bosonic and fermionic systems, that work by mapping the system's density matrix to a quasi-probability density and the Liouville-von Neumann equation of the Hamiltonian to a corresponding density differenti...
cond-mat_quant-gas
Strong Boundary and Trap Potential Effects on Emergent Physics in Ultra-Cold Fermionic Gases: The field of quantum simulations in ultra-cold atomic gases has been remarkably successful. In principle it allows for an exact treatment of a variety of highly relevant lattice models and their emergent phases of matter. Bu...
cond-mat_quant-gas
The response to dynamical modulation of the optical lattice for fermions in the Hubbard model: Fermionic atoms in a periodic optical lattice provide a realization of the single-band Hubbard model. Using Quantum Monte Carlo simulations along with the Maximum Entropy Method, we evaluate the effect of a time-dependent p...
cond-mat_quant-gas
Decoherence of an impurity in a one-dimensional fermionic bath with mass imbalance: We study the transport, decoherence and dissipation of an impurity interacting with a bath of free fermions in a one-dimensional lattice. Numerical simulations are made with the time-evolving block decimation method. We introduce a ma...
cond-mat_quant-gas
Rotating Fulde-Ferrell-Larkin-Ovchinnikov state in cold Fermi gases: We study an effect of rotation on the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state of two component Fermi superfluid gases in a toroidal trap. We investigate a stability of the FFLO states in the quasi-one-dimensional regime on the basis of the Bogol...
cond-mat_quant-gas
Bloch oscillations of spin-orbit-coupled cold atoms in an optical lattice and spin current generation: We study the Bloch oscillation dynamics of a spin-orbit-coupled cold atomic gas trapped inside a one-dimensioanl optical lattice. The eigenspectra of the system is identified as two interpenetrating Wannier-Stark la...
cond-mat_quant-gas
Mixtures of ultra-cold atoms in 1D disordered potentials: We study interacting 1D two-component mixtures of cold atoms in a random potential, and extend the results reported earlier [{\it Phys. Rev. Lett.} {\bf 105}, 115301 (2010)]. We construct the phase diagram of a disordered Bose-Fermi mixture as a function of the ...
cond-mat_quant-gas
Lattice bosons with infinite range checkerboard interactions: Motivated by experiments performed by Landig et al. [Nature 532, 476-479], we consider a two dimensional Bose gas in an optical lattice, trapped inside a single mode superradiant Fabry Perot cavity. The cavity mediates infinite range checkerboard interaction...
cond-mat_quant-gas
Theory of Non-Hermitian Fermionic Superfluidity with a Complex-Valued Interaction: Motivated by recent experimental advances in ultracold atoms, we analyze a non-Hermitian (NH) BCS Hamiltonian with a complex-valued interaction arising from inelastic scattering between fermions. We develop a mean-field theory to obtai...
cond-mat_quant-gas
Quantum phases in spin-orbit-coupled Floquet spinor Bose gases: We propose a spin-orbit-coupled Floquet spinor Bose-Einstein condensate (BEC) which can be implemented by Floquet engineering of a quadratic Zeeman field. The Floquet spinor BEC has a Bessel-function-modulated Rabi frequency and a Floquet-induced spin-exch...
cond-mat_quant-gas
First-order superfluid to Mott-insulator phase transitions in spinor condensates: We observe evidence of first-order superfluid to Mott-insulator quantum phase transitions in a lattice-confined antiferromagnetic spinor Bose-Einstein condensate. The observed signatures include hysteresis effect and significant heating...
cond-mat_quant-gas