Bogoliubov sound speed in periodically modulated Bose-Einstein condensates
Soft Condensed Matter
2012-05-10 v1 Statistical Mechanics
Abstract
We study the Bogoliubov excitations of a Bose-condensed gas in an optical lattice. Of primary interest is the long wavelength phonon dispersion for both current-free and current-carrying condensates. We obtain the dispersion relation by carrying out a systematic expansion of the Bogoliubov equations in powers of the phonon wave vector. Our result for the current-carrying case agrees with the one recently obtained by means of a hydrodynamic theory.
Keywords
Cite
@article{arxiv.cond-mat/0308194,
title = {Bogoliubov sound speed in periodically modulated Bose-Einstein condensates},
author = {E. Taylor and E. Zaremba},
journal= {arXiv preprint arXiv:cond-mat/0308194},
year = {2012}
}
Comments
16 pages, no figures