Phase separation and collapse in Bose-Fermi mixtures with a Feshbach resonance

TL;DR

This paper investigates the complex phase behavior of Bose-Fermi mixtures near a Feshbach resonance, revealing diverse phase-separated states and critical phenomena through a mean-field analysis, with implications for experimental collapse observations.

Contribution

It introduces a comprehensive mean-field model for Bose-Fermi mixtures near Feshbach resonances, uncovering a rich phase diagram with novel phase separation and critical points.

Findings

Identification of multiple phase-separated states.

Presence of critical and tricritical points.

Predictions for experimental collapse behavior.

Abstract

We consider a mixture of single-component bosonic and fermionic atoms with an interspecies interaction that is varied using a Feshbach resonance. By performing a mean-field analysis of a two-channel model, which describes both narrow and broad Feshbach resonances, we find an unexpectedly rich phase diagram at zero temperature: Bose-condensed and non-Bose-condensed phases form a variety of phase-separated states that are accompanied by both critical and tricritical points. We discuss the implications of our results for the experimentally observed collapse of Bose-Fermi mixtures on the attractive side of the Feshbach resonance, and we make predictions for future experiments on Bose-Fermi mixtures close to a Feshbach resonance.