A VARIATION PATH-INTEGRAL APPROACH TO THE THERMODYNAMICAL PROPERTIES OF A FINITE NUMBER OF TRAPPED RB-87 ATOMS

A variational path integral approach for a system of identical particl es is presented which allows the incorporation of two-body interaction s into the description of the thermodynamics of a confined Bose gas, u sing the propagators of a harmonic trial system. This approach combine s the statistical mechanics of bosons with equally spaced energy level s with the field-theoretical methods used in the Gross-Pitaevskii equa tion, bridging the characteristics of both theories and supporting the conclusions reached on the basis of a two-fluid model for Rb. (C) 199 8 Elsevier Science Ltd. All rights reserved.