Critical Temperature and Thermodynamics of Attractive Fermions at Unitarity

TL;DR

This paper uses diagrammatic determinant Monte Carlo to accurately determine the critical temperature and thermodynamic properties of attractive fermions at unitarity, providing insights into ultracold Fermi gases.

Contribution

It presents the first systematic-error-free finite-temperature simulation of the unitarity regime of attractive fermions, accurately calculating the critical temperature in units of Fermi energy.

Findings

Critical temperature T_c / E_F = 0.152(7)

Behavior of thermodynamic functions analyzed

Discussion on thermometry of ultracold Fermi gases

Abstract

The unitarity regime of the BCS-BEC crossover can be realized by diluting a system of two-component lattice fermions with an on-site attractive interaction. We perform a systematic-error-free finite-temperature simulations of this system by diagrammatic determinant Monte Carlo. The critical temperature in units of Fermi energy is found to be T_c / E_F = 0.152(7). We also report the behavior of the thermodynamic functions, and discuss the issues of thermometry of ultracold Fermi gases.