text
stringlengths
89
2.49k
category
stringclasses
19 values
Driven-dissipative Ising model: Dynamical crossover at weak dissipation: Driven quantum systems coupled to an environment typically exhibit effectively thermal behavior with relaxational dynamics near criticality. However, a different qualitative behavior might be expected in the weakly dissipative limit due to the com...
cond-mat_quant-gas
Quasi-one-dimensional flow of polariton condensate past an obstacle: Nonlinear wave patterns generated by the flow of polariton condensate past an obstacle are studied for quasi-one-dimensional microcavity geometry. It is shown that pumping and nonlinear damping play a crucial role in this process leading to sharp diff...
cond-mat_quant-gas
Staggered superfluid phases of dipolar bosons in two-dimensional square lattices: We study the quantum ground state of ultracold bosons in a two-dimensional square lattice. The bosons interact via the repulsive dipolar interactions and s-wave scattering. The dynamics is described by the extended Bose-Hubbard model in...
cond-mat_quant-gas
BCS-BCS crossover between atomic and molecular superfluids in a Bose-Fermi mixture: We theoretically examine a continuity between atomic and molecular Fermi superfluids in a Bose-Fermi mixture near the Feshbach resonance. Considering a two-channel model describing the Feshbach resonance between Fermi and Bose atoms, ...
cond-mat_quant-gas
Fulde-Ferrell superfluids in spinless ultracold Fermi gases: The Fulde-Ferrell (FF) superfluid phase, in which fermions form finite-momentum Cooper pairings, is well studied in spin-singlet superfluids in past decades. Different from previous works that engineer the FF state in spinful cold atoms, we show that the FF s...
cond-mat_quant-gas
Reply to the correspondence of Drummond and Brand [arXiv:1610.07633]: In their correspondence [arXiv:1610.07633] Drummond and Brand criticize our work [Nature Physics 12, 451-454 (2016) http://dx.doi.org/10.1038/nphys3631]. We show that their criticism is misleading and unfounded.
cond-mat_quant-gas
Dynamics of Uniform Quantum Gases, I: Density and Current Correlations: A unified approach valid for any wavenumber, frequency, and temperature is presented for uniform ideal quantum gases allowing for a comprehensive study of number density and particle-current density response functions. Exact analytical expressions ...
cond-mat_quant-gas
A long-lived Higgs mode in a two-dimensional confined Fermi gas: The Higgs mode corresponds to the collective motion of particles due to the vibrations of an invisible field. It plays a fundamental role for our understanding of both low and high energy physics, giving elementary particles their mass and leading to coll...
cond-mat_quant-gas
Critical Dynamics of a Two-dimensional Superfluid near a Non-Thermal Fixed Point: Critical dynamics of an ultracold Bose gas far from equilibrium is studied in two spatial dimensions. Superfluid turbulence is created by quenching the equilibrium state close to zero temperature. Instead of immediately re-thermalizing,...
cond-mat_quant-gas
A superfluid-droplet crystal and a free-space supersolid in a dipole-blockaded gas: A novel supersolid phase is predicted for an ensemble of Rydberg atoms in the dipole-blockade regime, interacting via a repulsive dipolar potential "softened" at short distances. Using exact numerical techniques, we study the low temp...
cond-mat_quant-gas
Atom chips with free-standing two-dimensional electron gases: advantages and challenges: In this work we consider the advantages and challenges of using free-standing two-dimensional electron gases (2DEG) as active components in atom chips for manipulating ultracold ensembles of alkali atoms. We calculate trapping pa...
cond-mat_quant-gas
Supersolid and charge density-wave states from anisotropic interaction in an optical lattice: We show anisotropy of the dipole interaction between magnetic atoms or polar molecules can stabilize new quantum phases in an optical lattice. Using a well controlled numerical method based on the tensor network algorithm, w...
cond-mat_quant-gas
Bound states in a quasi-two-dimensional Fermi gas: We consider the problem of N identical fermions of mass M and one distinguishable particle of mass m interacting via short-range interactions in a confined quasi-two-dimensional (quasi-2D) geometry. For N=2 and mass ratios M/m<13.6, we find non-Efimov trimers that smoo...
cond-mat_quant-gas
Collective excitations in two-dimensional harmonically trapped quantum droplets: The collective excitation modes in quantum droplets trapped in a two-dimensional harmonic potential in the context of symmetric weakly interacting binary bosonic mixtures are studied. By utilizing the linearization technique, the time-de...
cond-mat_quant-gas
Loosely Bound Few-Body States in a Spin-1 Gas with Near-Degenerate Continua: A distinguishing feature of ultracold collisions of bosonic lithium atoms is the presence of two near-degenerate two-body continua. The influence of such a near-degeneracy on the few-body physics in the vicinity of a narrow Feshbach resonanc...
cond-mat_quant-gas
Quantum vortex instability and black hole superradiance: Vortices and black holes set the scene for many interesting dynamical processes in physics. Here, we study the dynamical instability of quantised vortices and rotational superradiance around rotating black holes, illustrating in the process that the same physics ...
cond-mat_quant-gas
An exact formalism for the quench dynamics of integrable models: We describe a formulation for studying the quench dynamics of integrable systems generalizing an approach by Yudson. We study the evolution of the Lieb-Liniger model, a gas of interacting bosons moving on the continuous infinite line and interacting via a...
cond-mat_quant-gas
Open source Matrix Product States: Opening ways to simulate entangled many-body quantum systems in one dimension: Numerical simulations are a powerful tool to study quantum systems beyond exactly solvable systems lacking an analytic expression. For one-dimensional entangled quantum systems, tensor network methods, am...
cond-mat_quant-gas
Thermalization and Bose-Einstein condensation of quantum light in bulk nonlinear media: We study the thermalization and the Bose-Einstein condensation of a paraxial, spectrally narrow beam of quantum light propagating in a lossless bulk Kerr medium. The spatiotemporal evolution of the quantum optical field is ruled b...
cond-mat_quant-gas
Unitary $p$-wave Fermi gas in one dimension: We elucidate universal many-body properties of a one-dimensional, two-component ultracold Fermi gas near the $p$-wave Feshbach resonance. The low-energy scattering in this system can be characterized by two parameters, that is, $p$-wave scattering length and effective range....
cond-mat_quant-gas
Spatial separation of rotating binary Bose-Einstein condensate by tuning the dipolar interactions: We are pointing out relevant anisotropic effects, related to spatial separation, miscibility and mass-symmetry, due to dipole-dipole interactions in rotating binary dipolar Bose-Einstein condensates, by considering symm...
cond-mat_quant-gas
Spectrum of elementary excitations in Galilean-invariant integrable models: The spectrum of elementary excitations in one-dimensional quantum liquids is generically linear at low momenta. It is characterized by the sound velocity that can be related to the ground state energy. Here we study the spectrum at higher mom...
cond-mat_quant-gas
Dynamics of polar-core spin vortices in a ferromagnetic spin-1 Bose-Einstein condensate: A ferromagnetic spin-1 condensate supports polar-core spin vortices (PCVs) in the easy-plane phase. We derive a model for the dynamics of these PCVs using a variational Lagrangian approach. The PCVs behave as massive charged part...
cond-mat_quant-gas
Cooperative scattering measurement of coherence in a spatially modulated Bose gas: Correlations of a Bose gas released from an optical lattice are measured using superradiant scattering. Conditions are chosen so that after initial incident light pumping at the Bragg angle for diffraction, due to matter wave amplifica...
cond-mat_quant-gas
Light-cone effect and supersonic correlations in one- and two-dimensional bosonic superfluids: We study the spreading of density-density correlations in Bose-Hubbard models after a quench of the interaction strength, using time-dependent variational Monte Carlo simulations. It gives access to unprecedented long propa...
cond-mat_quant-gas
Two- and one-dimensional gap solitons in spin-orbit-coupled systems with Zeeman splitting: We elaborate a mechanism for the formation of stable solitons of the semi-vortex type (with vorticities 0 and 1 in their two components), populating a finite bandgap in the spectrum of the spin-orbit-coupled binary Bose-Einstei...
cond-mat_quant-gas
A Quantum Gas Microscope for Fermionic Atoms: Strongly interacting fermions define the properties of complex matter at all densities, from atomic nuclei to modern solid state materials and neutron stars. Ultracold atomic Fermi gases have emerged as a pristine platform for the study of many-fermion systems. Here we real...
cond-mat_quant-gas
Efimovian three-body potential from broad to narrow Feshbach resonances: We analyse the change in the hyperradial Efimovian three-body potential as the two-body interaction is tuned from the broad to narrow Feshbach resonance regime. Here, it is known from both theory and experiment that the three-body dissociation sca...
cond-mat_quant-gas
Many-body Dynamics with Time-dependent Interaction: Recent advances in optical Feshbach resonance technique have enabled the experimental investigation of atomic gases with time-dependent interaction. In this work, we study the many-body dynamics of weakly interacting bosons subject with an arbitrary time varying scatt...
cond-mat_quant-gas
Dynamical Zeeman resonance in spin-orbit-coupled spin-1 Bose gases: We predict a dynamical resonant effect, which is driven by externally applied linear and quadratic Zeeman fields, in a spin-orbit-coupled spin-1 Bose-Einstein condensate. The Bose-Einstein condensate is assumed to be initialized in some superposed stat...
cond-mat_quant-gas
Entanglement structure of a quantum simulator: the two-component Bose-Hubbard model: We consider a quantum simulator of the Heisenberg chain with ferromagnetic interactions based on the two-component 1D Bose-Hubbard model at filling equal to two in the strong coupling regime. The entanglement properties of the ground...
cond-mat_quant-gas
Finite-momentum Bose-Einstein condensates in shaken 2D square optical lattices: We consider ultracold bosons in a 2D square optical lattice described by the Bose-Hubbard model. In addition, an external time-dependent sinusoidal force is applied to the system, which shakes the lattice along one of the diagonals. The e...
cond-mat_quant-gas
Nonequilibrium Phase Diagram of a Driven-Dissipative Many-Body System: We study the nonequilibrium dynamics of a many-body bosonic system on a lattice, subject to driving and dissipation. The time-evolution is described by a master equation, which we treat within a generalized Gutzwiller mean field approximation for de...
cond-mat_quant-gas
Cooling and Near-equilibrium Dynamics of Atomic Gases Across the Superfluid-Mott Insulator Transition: We study near-equilibrium thermodynamics of bosonic atoms in a two-dimensional optical lattice by ramping up the lattice depth to convert a superfluid into an inhomogeneous mixture of superfluid and Mott insulator. ...
cond-mat_quant-gas
Pi-phases in balanced fermionic superfluids on spin-dependent optical lattices: We study a balanced two-component system of ultracold fermions in one dimension with attractive interactions and subject to a spin-dependent optical lattice potential of opposite sign for the two components. We find states with different ...
cond-mat_quant-gas
Dipolar dark solitons: We numerically generate, and then study the basic properties of dark soliton-like excitations in a dipolar gas confined in a quasi one dimensional trap. These excitations, although very similar to dark solitons in a gas with contact interaction, interact with each other and can form bound states....
cond-mat_quant-gas
Entanglement spectrum and quantum phase diagram of the long-range XXZ chain: Entanglement is a central feature of many-body quantum systems and plays a unique role in quantum phase transitions. In many cases, the entanglement spectrum, which represents the spectrum of the density matrix of a bipartite system, conta...
cond-mat_quant-gas
Transition between vacuum and finite-density states in the infinite-dimensional Bose-Hubbard model with spatially inhomogeneous dissipation: We analyze dynamics of the infinite-dimensional Bose-Hubbard model with spatially inhomogeneous dissipation in the hardcore boson limit by solving the Lindblad master equation...
cond-mat_quant-gas
Non-degenerate Bound State Solitons in Multi-component Bose-Einstein Condensates: We investigate non-degenerate bound state solitons systematically in multi-component Bose-Einstein condensates, through developing Darboux transformation method to derive exact soliton solutions analytically. In particular, we show that...
cond-mat_quant-gas
Dynamics of polar-core spin vortices in a ferromagnetic spin-1 Bose-Einstein condensate: A ferromagnetic spin-1 condensate supports polar-core spin vortices (PCVs) in the easy-plane phase. We derive a model for the dynamics of these PCVs using a variational Lagrangian approach. The PCVs behave as massive charged part...
cond-mat_quant-gas
Site-resolved imaging of a fermionic Mott insulator: The complexity of quantum many-body systems originates from the interplay of strong interactions, quantum statistics, and the large number of quantum-mechanical degrees of freedom. Probing these systems on a microscopic level with single-site resolution offers import...
cond-mat_quant-gas
Weyl points and topological nodal superfluids in a face-centered cubic optical lattice: We point out that a face-centered cubic (FCC) optical lattice, which can be realised by a simple scheme using three lasers, provides one a highly controllable platform for creating Weyl points and topological nodal superfluids in ...
cond-mat_quant-gas
Comment on: `Single-shot simulations of dynamic quantum many-body systems' [arXiv:1501.03224]: In their recent paper [Nature Physics 15, 451 (2006)], Sakmann and Kasevich study the formation of fringe patterns in ultra-cold Bose gases and claim: `Here, we show how single shots can be simulated from numerical solution...
cond-mat_quant-gas
Tuning photon-mediated interactions in a multimode cavity: from supersolid to insulating droplets hosting phononic excitations: Ultracold atoms trapped in laser-generated optical lattices serve as a versatile platform for quantum simulations. However, as these lattices are infinitely stiff, they do not allow to emula...
cond-mat_quant-gas
Dark soliton oscillations in Bose-Einstein condensates with multi-body interactions: We consider the dynamics of dark matter solitons moving through non-uniform cigar-shaped Bose-Einstein condensates described by the mean field Gross-Pitaevskii equation with generalized nonlinearities, in the case when the condition ...
cond-mat_quant-gas
A Renormalization-Group Study of Interacting Bose-Einstein Condensates: II. Anomalous Dimension $η$ for $d\lesssim 4$ at Finite Temperatures: We study the anomalous dimension $\eta$ of homogeneous interacting single-component Bose-Einstein condensates at finite temperatures for $d\lesssim 4$ dimensions. This $\eta$ i...
cond-mat_quant-gas
Quasi-one-dimensional spin-orbit- and Rabi-coupled bright dipolar Bose-Einstein-condensate solitons: We study the formation of stable bright solitons in quasi-one-dimensional (quasi-1D) spin-orbit- (SO-) and Rabi-coupled two pseudospinor dipolar Bose-Einstein condensates (BECs) of 164 Dy atoms in the presence of repu...
cond-mat_quant-gas
Transition state theory for wave packet dynamics. II. Thermal decay of Bose-Einstein condensates with long-range interaction: We apply transition state theory to coupled Gaussian wave packets and calculate thermal decay rates of Bose-Einstein condensates with additional long-range interaction. The ground state of suc...
cond-mat_quant-gas
Many-particle Quantum Hydrodynamics of Spin-1 Bose-Einstein Condensates: We develop a novel model of the magnetized spin-1 Bose-Einstein condensate (BEC) of neutral atoms, using the method of many-particle quantum hydrodynamic (QHD) and propose an original derivation of the system of continual equations. We consider bo...
cond-mat_quant-gas
Interference dynamics of matter-waves of SU($N$) fermions: We analyze the two main physical observables related to the momenta of strongly correlated SU($N$) fermions in ring-shaped lattices pierced by an effective magnetic flux: homodyne (momentum distribution) and self-heterodyne interference patterns. We demonstrate...
cond-mat_quant-gas
Counter-propagating edge modes and topological phases of a kicked quantum Hall system: A periodically driven quantum Hall system in a fixed magnetic field is found to exhibit a series of phases featuring anomalous edge modes with the "wrong" chirality. This leads to pairs of counter-propagating chiral edge modes at e...
cond-mat_quant-gas
Mesoscopic quantum switching of a Bose-Einstein condensate in an optical lattice governed by the parity of the number of atoms: It is shown that for a $N$-boson system the parity of $N$ can be responsible for a qualitative difference in the system response to variation of a parameter. The nonlinear boson model is con...
cond-mat_quant-gas
Breaking of Goldstone modes in two component Bose-Einstein condensate: We study the decay rate $\Gamma(k)$ of density excitations of two-component Bose-Einstein condensates at zero temperature. Those excitations, where the two components oscillate in phase, include the Goldstone mode resulting from condensation. While ...
cond-mat_quant-gas
Magnetic Phase Transition in the Ground-State Phase Diagram of Binary Bose Gases in Optical Lattices: We investigate the ground-state phase diagram of interacting binary Bose gases trapped in two-dimensional optical lattices by means of quantum Monte Carlo simulations. Our simulations reveal a magnetic phase transiti...
cond-mat_quant-gas
Charge density wave and charge pump of interacting fermions in circularly shaken hexagonal optical lattices: We analyze strong correlation effects and topological properties of interacting fermions with a Falicov-Kimball type interaction in circularly shaken hexagonal optical lattices, which can be effectively descri...
cond-mat_quant-gas
Zero-temperature equation of state of mass-imbalanced resonant Fermi gases: We calculate the zero-temperature equation of state of mass-imbalanced resonant Fermi gases in an ab initio fashion, by implementing the recent proposal of imaginary-valued mass difference to bypass the sign problem in lattice Monte Carlo cal...
cond-mat_quant-gas
Quantum Field Theory of Correlated Bose-Einstein condensates: I. Basic Formalism: Quantum field theory of equilibrium and nonequilibrium Bose-Einstein condensates is formulated so as to satisfy three basic requirements: the Hugenholtz-Pines relation; conservation laws; identities among vertices originating from Golds...
cond-mat_quant-gas
Stability and dynamics across magnetic phases of vortex-bright type excitations in spinor Bose-Einstein condensates: The static properties, i.e., existence and stability, as well as the quench-induced dynamics of vortex-bright type excitations in two-dimensional harmonically confined spin-1 Bose-Einstein condensates ...
cond-mat_quant-gas
A Strongly Interacting Polaritonic Quantum Dot: Polaritons are an emerging platform for exploration of synthetic materials [1] and quantum information processing [2] that draw properties from two disparate particles: a photon and an atom. Cavity polaritons are particularly promising, as they are long-lived and their di...
cond-mat_quant-gas
Dark-Bright Solitons in a Superfluid Bose-Fermi Mixture: The recent experimental realization of Bose-Fermi superfluid mixtures of dilute ultracold atomic gases has opened new perspectives in the study of quantum many-body systems. Depending on the values of the scattering lengths and the amount of bosons and fermions, ...
cond-mat_quant-gas
Two-dimensional scattering and bound states of polar molecules in bilayers: Low-energy two-dimensional scattering is particularly sensitive to the existence and properties of weakly-bound states. We show that interaction potentials $V(r)$ with vanishing zero-momentum Born approximation $\int d^2r V(r)=0$ lead to an a...
cond-mat_quant-gas
First-order spatial coherence measurements in a thermalized two-dimensional photonic quantum gas: Phase transitions between different states of matter can profoundly modify the order in physical systems, with the emergence of ferromagnetic or topological order constituting important examples. Correlations allow to qu...
cond-mat_quant-gas
Dark-soliton-like excitations in the Yang-Gaudin gas of attractively interacting fermions: Yrast states are the lowest energy states at given non-zero momentum and provide a natural extension of the concept of dark solitons to strongly-interacting one-dimensional quantum gases. Here we study the yrast states of the b...
cond-mat_quant-gas
Superfluidity and Stabilities of a Bose-Einstein condensate with periodically modulated interatomic interaction: We study theoretically the superfluidity and stability of a Bose-Einstein condensate (BEC) whose interatomic scattering length is periodically modulated with optical Feshbach resonance. Our numerical study...
cond-mat_quant-gas
Bose-Einstein Condensates in Non-abelian Gauge Fields: The recent success of the NIST group in generating abelian gauge field in cold atoms has created opportunities to simulate electronic transports in solids using atomic gases. Very recently, the NIST group has also announced in a DARPA Meeting the creation of non-ab...
cond-mat_quant-gas
Three-level Haldane-like model on dice optical lattice: We consider ultracold atoms in a two-dimensional optical lattice of the dice geometry in a tight-binding regime. The atoms experience a laser-assisted tunneling between the nearest neighbour sites of the dice lattice accompanied by the momentum recoil. This allows...
cond-mat_quant-gas
(Inverse) Magnetic Catalysis in Bose-Einstein Condensation of Neutral Bound Pairs: The Bose-Einstein condensation of bound pairs made of oppositely charged fermions in a magnetic field is investigated. We find that the condensation temperature shows the magnetic catalysis effect in weak coupling and the inverse magne...
cond-mat_quant-gas
Synchronization transition in dipole-coupled two-level systems with positional disorder: We study the decoherence dynamics of dipole-coupled two-level quantum systems in Ramsey-type experiments. We focus on large networks of two-level systems, confined to two spatial dimensions and with positional disorder giving ris...
cond-mat_quant-gas
Strong optical self-focusing effect in coherent light scattering with condensates: We present a theoretical investigation of optical self-focusing effects in light scattering with condensates. Using long (>200 \mu s), red-detuned pulses we show numerically that a non-negligible self-focusing effect is present that ca...
cond-mat_quant-gas
Confinement-induced collapse of a dipolar Bose-Einstein condensate: We report on the observation of the confinement-induced collapse dynamics of a dipolar Bose-Einstein condensate (dBEC) in a one-dimensional optical lattice. We show that for a fixed interaction strength the collapse can be initiated in-trap by lowering...
cond-mat_quant-gas
Design and construction of a quantum matter synthesizer: The quantum matter synthesizer (QMS) is a new quantum simulation platform in which individual particles in a lattice can be resolved and re-arranged into arbitrary patterns. The ability to spatially manipulate ultracold atoms and control their tunneling and inter...
cond-mat_quant-gas
Excitation spectrum of a mixture of two Bose gases confined in a ring potential with interaction asymmetry: We study the rotational properties of a two-component Bose-Einstein condensed gas of distinguishable atoms which are confined in a ring potential using both the mean-field approximation, as well as the method o...
cond-mat_quant-gas
Disordered structures in ultracold spin-imbalanced Fermi gas: We investigate properties of spin-imbalanced ultracold Fermi gas in a large range of spin polarizations at low temperatures. We present results of microscopic calculations based on mean-field and density functional theory approaches, with no symmetry constra...
cond-mat_quant-gas
Thermal suppression of demixing dynamics in a binary condensate: We investigate the demixing dynamics in a binary two-dimensional (2D) Bose superfluid using classical-field dynamics. By quenching the interspecies interaction parameter, we identify a strong and weak separation regime depending on the system temperature ...
cond-mat_quant-gas
Dynamical transitions and quantum quenches in mean-field models: We develop a generic method to compute the dynamics induced by quenches in completely connected quantum systems. These models are expected to provide a mean-field description at least of the short time dynamics of finite dimensional system. We apply our m...
cond-mat_quant-gas
Cavity-enhanced optical lattices for scaling neutral atom quantum technologies to higher qubit numbers: We demonstrate a cavity-based solution to scale up experiments with ultracold atoms in optical lattices by an order of magnitude over state-of-the-art free space lattices. Our two-dimensional optical lattices are c...
cond-mat_quant-gas
Goldstone mode and pair-breaking excitations in atomic Fermi superfluids: Spontaneous symmetry breaking is a central paradigm of elementary particle physics, magnetism, superfluidity and superconductivity. According to Goldstone's theorem, phase transitions that break continuous symmetries lead to the existence of gapl...
cond-mat_quant-gas
Energy Cascade in Quantum Gases: Energy cascade is ubiquitous in systems far from equilibrium. Facilitated by particle interactions and external forces, it can lead to highly complex phenomena like fully developed turbulence, characterized by power law velocity correlation functions. Yet despite decades of research, ho...
cond-mat_quant-gas
Induced supersolidity in a Dy-Er mixture: Recent experimental realization of the heteronuclear dipolar mixture of Dy and Er atoms opens fascinating prospects for creating intriguing novel phases in dipolar quantum gases. The experimentally measured value of intra-species $s$-wave scattering length of $^{166}$Er condens...
cond-mat_quant-gas
A continuum of compass spin models on the honeycomb lattice: Quantum spin models with spatially dependent interactions, known as compass models, play an important role in the study of frustrated quantum magnetism. One example is the Kitaev model on the honeycomb lattice with spin-liquid ground states and anyonic excita...
cond-mat_quant-gas
Finite temperature theory of superfluid bosons in optical lattices: A practical finite temperature theory is developed for the superfluid regime of a weakly interacting Bose gas in an optical lattice with additional harmonic confinement. We derive an extended Bose-Hubbard model that is valid for shallow lattices and wh...
cond-mat_quant-gas
The one-dimensional Bose gas with strong two-body losses: the effect of the harmonic confinement: We study the dynamics of a one-dimensional Bose gas in presence of strong two-body losses. In this dissipative quantum Zeno regime, the gas fermionises and its dynamics can be described with a simple set of rate equation...
cond-mat_quant-gas
Dynamics of spin-polarized impurity in ultracold Fermi gas: We show that the motion of spin-polarized impurity (ferron) in ultracold atomic gas is characterized by a certain critical velocity which can be traced back to the amount of spin imbalance inside the impurity. We have calculated the effective mass of ferron in...
cond-mat_quant-gas
Dimensional crossover and cold-atom realization of topological Mott insulators: We propose a cold-atom setup which allows for a dimensional crossover from a two-dimensional quantum spin Hall insulating phase to a three-dimensional strong topological insulator by tuning the hopping between the layers. We further show ...
cond-mat_quant-gas
Spontaneous Magnetic Ordering in a Ferromagnetic Spinor Dipolar Bose-Einstein Condensate: We study the spin dynamics in a spin-1 ferromagnetic Bose-Einstein condensate with magnetic dipole-dipole interaction (MDDI) based on the Gross-Pitaevskii and Bogoliubov theories. We find that various magnetic structures such as...
cond-mat_quant-gas
Three-body scattering area for particles with infinite or zero scattering length in two dimensions: We derive the asymptotic expansions of the wave function of three particles having equal mass with finite-range interactions and infinite or zero two-dimensional scattering length colliding at zero energy and zero orbi...
cond-mat_quant-gas
Nature of polaron-molecule transition in Fermi polarons: In this work, we explore the polaron and molecule physics by utilizing a unified variational ansatz with up to two particle-hole(p-h) excitations(V-2ph). We confirm the existence of a first-order transition in 3D and 2D Fermi polarons, and show that the nature of...
cond-mat_quant-gas
Observation of a two-dimensional Fermi gas of atoms: We have prepared a degenerate gas of fermionic atoms which move in two dimensions while the motion in the third dimension is "frozen" by tight confinement and low temperature. {\it In situ} imaging provides direct measurement of the density profile and temperature. T...
cond-mat_quant-gas
Long-range sound-mediated dark soliton interactions in trapped atomic condensates: A long-range soliton interaction is discussed whereby two or more dark solitons interact in an inhomogeneous atomic condensate, modifying their respective dynamics via the exchange of sound waves without ever coming into direct contact...
cond-mat_quant-gas
Supersolid-like square- and honeycomb-lattice crystallization of droplets in a dipolar condensate: We demonstrate a supersolid-like spatially-periodic square- and honeycomb-lattice crystallization of droplets, in addition to the commonly-studied triangular-lattice crystallization, in a cylindrically-symmetric quasi-t...
cond-mat_quant-gas
The self-energy of an impurity in an ideal Fermi gas to second order in the interaction strength: We study in three dimensions the problem of a spatially homogeneous zero-temperature ideal Fermi gas of spin-polarized particles of mass $m$ perturbed by the presence of a single distinguishable impurity of mass $M$. The...
cond-mat_quant-gas
Many-body tunneling dynamics of Bose-Einstein condensates and vortex states in two spatial dimensions: In this work, we study the out-of-equilibrium many-body tunneling dynamics of a Bose-Einstein condensate in a two-dimensional radial double well. We investigate the impact of interparticle repulsion and compare the ...
cond-mat_quant-gas
Vortex annihilation and inverse cascades in two dimensional superfluid turbulence: We study two dimensional superfluid turbulence by employing an effective description valid in the limit where the density of superfluid vortices is parametrically small. At sufficiently low temperatures the effective description yields...
cond-mat_quant-gas
Quantum phase diagram for two species hardcore bosons in one-dimensional optical lattices with the resonantly driven Rabi frequency: We propose an experimental realization of the time-periodically modulated Rabi frequency and suggest density-dependent hoppings of two species hardcore bosons in a one-dimensional optic...
cond-mat_quant-gas
Bogoliubov excitation spectrum of an elongated condensate from quasi-one-dimensional to three-dimensional transition: The quasiparticle excitation spectra of a Bose gas trapped in a highly anisotropic trap is studied with respect to varying total number of particles by numerically solving the effective one-dimensiona...
cond-mat_quant-gas
Universal Five- and Six-Body Droplets Tied to an Efimov Trimer: We explore the properties of weakly bound bosonic states in the strongly interacting regime. Combining a correlated-Gaussian (CG) basis set expansion with a complex scaling method, we extract the energies and structural properties of bosonic cluster states...
cond-mat_quant-gas
Optical Flux Lattices for Two-Photon Dressed States: We describe a simple scheme by which "optical flux lattices" can be implemented in ultracold atomic gases using two-photon dressed states. This scheme can be applied, for example, to the ground state hyperfine levels of commonly used atomic species. The resulting flu...
cond-mat_quant-gas
Topological bands with Chern number C=2 by dipolar exchange interactions: We demonstrate the realization of topological band structures by exploiting the intrinsic spin-orbit coupling of dipolar interactions in combination with broken time-reversal symmetry. The system is based on polar molecules trapped in a deep opti...
cond-mat_quant-gas
Z_2 Topological Insulators in Ultracold Atomic Gases: We describe how optical dressing can be used to generate bandstructures for ultracold atoms with non-trivial Z_2 topological order. Time reversal symmetry is preserved by simple conditions on the optical fields. We first show how to construct optical lattices that g...
cond-mat_quant-gas
High-precision numerical solution of the Fermi polaron problem and large-order behavior of its diagrammatic series: We introduce a simple determinant diagrammatic Monte Carlo algorithm to compute the ground-state properties of a particle interacting with a Fermi sea through a zero-range interaction. The fermionic sig...
cond-mat_quant-gas