Low-dimensional Bose gases
摘要
We present an improved many-body T-matrix theory for partially Bose-Einstein condensed atomic gases by treating the phase fluctuations exactly. The resulting mean-field theory is valid in arbitrary dimensions and able to describe the low-temperature crossover between three, two and one-dimensional Bose gases. When applied to a degenerate two-dimensional atomic hydrogen gas, we obtain a reduction of the three-body recombination rate which compares favorably with experiment. Supplementing the mean-field theory with a renormalization-group approach to treat the critical fluctuations, we also incorporate into the theory the Kosterlitz-Thouless transition that occurs in a homogeneous Bose gas in two dimensions. In particular, we calculate the critical conditions for the Kosterlitz-Thouless phase transition as a function of the microscopic parameters of the theory. The proposed theory is further applied to a trapped one-dimensional Bose gas, where we find good agreement with exact numerical results obtained by solving a nonlinear Langevin field equation.
引用
@article{arxiv.cond-mat/0202085,
title = {Low-dimensional Bose gases},
author = {U. Al Khawaja and J. O. Andersen and N. P. Proukakis and H. T. C Stoof},
journal= {arXiv preprint arXiv:cond-mat/0202085},
year = {2014}
}
备注
14 pages, 13 figures, revtex