Phase Transitions in Three-Dimensional Bosonic Systems in Optical Lattices
Quantum Gases
2014-01-22 v3
Abstract
We formulate the Collective Quantum Field Theory for three-dimensional bosonic optical lattices and evaluate its consequences in a mean-field approximation to two collective fields, proposed by Fred Cooper et al. and in a lowest-order Variational Perturbation Theory (VPT). It is shown that present mean-field approximation predicts some essential features of the experimentally observed dependence of the critical temperature on the coupling strength and a second - order quantum phase transition.In contrast to a recent prediction for atomic gases by Fred Cooper et. al., we find no superfluid state with zero condensate fraction.
Cite
@article{arxiv.1303.1642,
title = {Phase Transitions in Three-Dimensional Bosonic Systems in Optical Lattices},
author = {H. Kleinert and Z. Narzikulov and Abdulla Rakhimov},
journal= {arXiv preprint arXiv:1303.1642},
year = {2014}
}
Comments
21 pages, revtex, 4 figures. In this version the figures have been replaced, and the text extended