Condensation of Ideal Bose Gas Confined in a Box Within a Canonical Ensemble

Konstantin Glaum, Hagen Kleinert, Axel Pelster

Published 2007-07-18, updated 2007-12-12Version 2

We set up recursion relations for the partition function and the ground-state occupancy for a fixed number of non-interacting bosons confined in a square box potential and determine the temperature dependence of the specific heat and the particle number in the ground state. A proper semiclassical treatment is set up which yields the correct small-T-behavior in contrast to an earlier theory in Feynman's textbook on Statistical Mechanics, in which the special role of the ground state was ignored. The results are compared with an exact quantum mechanical treatment. Furthermore, we derive the finite-size effect of the system.