Quantum Monte Carlo Study of a Resonant Bose-Fermi Mixture

TL;DR

This study uses quantum Monte Carlo simulations to analyze a resonant Bose-Fermi mixture at zero temperature, revealing a quantum phase transition and mapping the phase diagram across interaction strengths and densities.

Contribution

It provides the first detailed quantum Monte Carlo analysis of phase transitions in a resonant Bose-Fermi mixture, including the equation of state and phase diagram.

Findings

First-order quantum phase transition identified

Phase separation region shrinks to zero as boson density vanishes

Equation of state and phase diagram characterized

Abstract

We study a resonant Bose-Fermi mixture at zero temperature by using the fixed-node diffusion Monte Carlo method. We explore the system from weak to strong boson-fermion interaction, for different concentrations of the bosons relative to the fermion component. We focus on the case where the boson density $n_B$ is smaller than the fermion density $n_F$, for which a first-order quantum phase transition is found from a state with condensed bosons immersed in a Fermi sea, to a Fermi-Fermi mixture of composite fermions and unpaired fermions. We obtain the equation of state and the phase diagram, and we find that the region of phase separation shrinks to zero for vanishing $n_B$.