Thermodynamics of a Trapped Bose-Fermi Mixture

TL;DR

This paper investigates the thermodynamic properties of a dilute trapped Bose-Fermi mixture using Hartree-Fock-Bogoliubov equations, revealing how attractive interactions enhance Bose-Einstein condensation.

Contribution

It introduces a detailed analysis of thermodynamics in Bose-Fermi mixtures within a harmonic trap, highlighting the effects of attractive and repulsive interactions on condensation.

Findings

Attractive Bose-Fermi interactions significantly increase condensate fraction.

Critical temperature for Bose-Einstein condensation is elevated with attraction.

Relevance to current experiments on Rb-K mixtures is discussed.

Abstract

By using the Hartree-Fock-Bogoliubov equations within the Popov approximation, we investigate the thermodynamic properties of a dilute binary Bose-Fermi mixture confined in an isotropic harmonic trap. For mixtures with an attractive Bose-Fermi interaction we find a sizable enhancement of the condensate fraction and of the critical temperature of Bose-Einstein condensation with respect to the predictions for a pure interacting Bose gas. Conversely, the influence of the repulsive Bose-Fermi interaction is less pronounced. The possible relevance of our results in current experiments on trapped $^{87}{\rm Rb}-^{40}${\rm K} mixtures is discussed.