Related papers: Cold Atoms in Driven Optical Lattices
The exact macroscopic wave functions of two-species Bose-Einstein condensates in an optical lattice beyond the tight-binding approximation are studied by solving the coupled nonlinear Schrodinger equations. The phase diagram for superfluid…
By means of the variational approximation (VA) and systematic simulations, we study dynamics and stability boundaries for solitons in a two-dimensional (2D) self-attracting Bose-Einstein condensate (BEC), trapped in an optical lattice (OL)…
In the present contribution, we explore a host of different stationary states, namely dark-bright solitons and their lattices, that arise in the context of multi-component atomic Bose-Einstein condensates. The latter, are modeled by systems…
We review our studies on Bose and Fermi superfluids of cold atomic gases in optical lattices at zero temperature. Especially, we focus on superfluid Fermi gases along the crossover between the Bardeen-Cooper-Schrieffer (BCS) and the…
The dynamics of a coupled Bose-Einstein condensate involving trapped atoms in two quantum states is studied using the time-dependent Gross-Pitaevskii equation including an interaction which can transform atoms from one state to the other.…
The Bloch and dipole oscillations of a Bose Einstein condensate (BEC) in an optical superlattice is investigated. We show that the effective mass increases in an optical superlattice, which leads to localization of the BEC, in accordance…
We consider matter-wave solitons in spin-orbit coupled Bose-Einstein condensates embedded in optical lattice and study dynamics of soliton within the framework of Gross-Pitaevskii equations. We express spin components of the soliton pair in…
We investigate a new type of quantum ratchet which may be realised by cold atoms in a double-well optical lattice which is pulsed with unequal periods. The classical dynamics is chaotic and we find the classical diffusion rate $D$ is…
Cold atoms confined in periodic potentials are remarkably versatile quantum systems for implementing simple models prevalent in condensed matter theory. In the current experiment, we realize the 2D Bose-Hubbard model by loading a…
We investigate the existence and especially the linear stability of single and multiple-charge quantized vortex states of nonlinear Schroedinger equations in the presence of a periodic and a parabolic potential in two spatial dimensions.…
Recent experiments have shown a remarkable number of collapse-and-revival oscillations of the matter-wave coherence of ultracold atoms in optical lattices [Will et al., Nature 465, 197 (2010)]. Using a mean-field approximation to the…
In response to a recent manuscript [cond-mat/0609685] on the analysis of interference patterns produced by ultracold atoms released from an optical lattice, we point out that in the presence of a Bose-Einstein condensate the interference…
We study the behavior of a Bose-Einstein condensate held in an optical lattice. We first show how a self-trapping transition can be induced in the system by either increasing the number of atoms occupying a lattice site, or by raising the…
We study the dynamics of strongly repulsive Bose gas in tilted or driven bichromatic optical lattices. Using the Bose-Fermi mapping and exact numerical method, we calculate the reduced single-particle density matrices, and study the…
Superfluids with strong spatial modulation can be experimentally produced in the area of cold atoms under the influence of optical lattices. Here we address $^{87}$Rb bosons at T=0 K in a flat geometry under the influence of a periodic…
We study the dynamics of Bose-Einstein condensates flowing in optical lattices on the basis of quantum field theory. For such a system, a Bose-Einstein condensate shows a unstable behavior which is called the dynamical instability. The…
We calculate the hydrodynamic solutions for a dilute Bose-Einstein condensate with long-range dipolar interactions in a rotating, elliptical harmonic trap, and analyse their dynamical stability. The static solutions and their regimes of…
We investigate the phase diffusion of a Bose-Einstein condensate (BEC) confined in the combined potential of a magnetic trap and a one-dimensional optical lattice. We show that the phase diffusion of the condensate in the whole optical…
Cold atoms in optical lattices allow for accurate studies of many body dynamics. Rapid time-dependent modifications of optical lattice potentials may result in significant excitations in atomic systems. The dynamics in such a case is…
We investigated non-equilibrium atomic dynamics in a moving optical lattice via observation of atomic resonance fluorescence spectrum. A three-dimensional optical lattice was generated in a phase-stabilized magneto-optical trap (MOT) and…