Effect of Weak Disorder on the BCS-BEC crossover in a two-dimensional Fermi Gas

TL;DR

This paper investigates how weak disorder influences the BCS-BEC crossover in a 2D ultracold Fermi gas, revealing that disorder can enhance superfluidity at the crossover point due to dimensional effects.

Contribution

It introduces a mean-field framework incorporating Gaussian fluctuations to analyze the impact of weak impurities on 2D Fermi gases during the BCS-BEC crossover.

Findings

Disorder enhances superfluidity at the crossover.

Impurity effects are studied through condensate fraction and equation of state.

Dimensional effects play a key role in the observed phenomena.

Abstract

In this article we study the two-dimensional (2D) ultracold Fermi gas with weak impurity in the framework of mean-field theory where the impurity is introduced through Gaussian fluctuations. We have investigated the role of the impurity by studying the experimentally accessible quantities such as condensate fraction and equation of state of the ultracold systems. Our analysis reveals that, at the crossover the disorder enhances superfluidity, which we attribute to the unique nature of the unitary region and to the dimensional effect.