Collective excitations of a trapped Bose-Einstein condensate in the presence of weak disorder and a two-dimensional optical lattice
arXiv:1004.3333 · doi:10.1103/PhysRevA.81.053621
Abstract
We investigate the combined effects of weak disorder and a two-dimensional (2D) optical lattice on the collective excitations of a harmonically trapped Bose-Einstein condensate (BEC) at zero temperature. Accordingly, we generalize the hydrodynamic equations of superfluid for a weakly interacting Bose gas in a 2D optical lattice to include the effects of weak disorder. Our analytical results for the collective frequencies beyond the mean-field approximation reveal the peculiar role of disorder, interplaying with the 2D optical lattice and interatomic interaction, on elementary excitations along the 3D to 1D dimensional crossover. In particular, consequences of disorder on the phonon propagation and surface modes are analyzed in detail. The experimental scenario is also proposed.
11 pages, no figures, accepted for publication in Physical Review A
References in corpus (17)
- Many-Body Physics with Ultracold Gases
- Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
- Disordered quantum gases under control
- Anderson Localization of Expanding Bose-Einstein Condensates in Random Potentials
- Localization of bosonic atoms by fermionic impurities in a 3d optical lattice
- Strongly interacting bosons in a disordered optical lattice
- Cold Bosons in Optical Lattices
- Bose-Einstein condensates in 1D optical lattices: compressibility, Bloch bands and elementary excitations
- Localization of Matter Waves in 2D-Disordered Optical Potentials
- Measuring the Superfluid Fraction of an Ultracold Atomic Gas
- Bose-Einstein-condensed gases in arbitrarily strong random potentials
- Superfluid to Bose-glass transition in a 1D weakly interacting Bose gas
- Bose-Einstein-condensed gases with arbitrary strong interactions
- Compression as a tool to detect Bose glass in cold atoms experiments
- Localized states and interaction induced delocalization in Bose gases with quenched disorder
- Quantum fluctuations and collective oscillations of a Bose-Einstein condensate in a 2D optical lattice
- Effects of disorder on quantum fluctuations and superfluid density of a Bose-Einstein condensate in a two-dimensional optical lattice
Cited by in corpus (5)
- Localization of Bogoliubov quasiparticles in interacting Bose gases with correlated disorder
- Optically trapped quasi-two-dimensional Bose gases in random environment: quantum fluctuations and superfluid density
- Unusual behavior of sound velocity of a Bose gas in an optical superlattice at quasi-one-dimension
- Cornwall-Jackiw-Tomboulis effective field theory to nonuniversal equation of state of an ultracold Bose gas
- Lattice-induced wavefunction effects on trapped superfluids