Landau functions for non-interacting bosons
Abstract
We discuss the statistics of Bose-Einstein condensation (BEC) in a canonical ensemble of N non-interacting bosons in terms of a Landau function L_N^{BEC} (q) defined by the logarithm of the probability distribution of the order parameter q for BEC. We also discuss the corresponding Landau function for spontaneous symmetry breaking (SSB), which for finite N should be distinguished from L_N^{BEC}. Only for intinite N BEC and SSB can be described by the same Landau function which depends on the dimensionality and on the form of the external potential in a surprisingly complex manner. For bosons confined by a three-dimensional harmonic trap the Landau function exhibits the usual behavior expected for continuous phase transitions.
Cite
@article{arxiv.cond-mat/0605138,
title = {Landau functions for non-interacting bosons},
author = {Andreas Sinner and Florian Schuetz and Peter Kopietz},
journal= {arXiv preprint arXiv:cond-mat/0605138},
year = {2007}
}
Comments
4 pages, 4 figures; final version to appear as a rapid communication in Physical Review A. Abstract modified and typos corrected