Phase diagrams of 2D and 3D disordered Bose gases in the local density approximation

TL;DR

This paper investigates superfluid transitions in 2D and 3D disordered Bose gases using the local density approximation, revealing that small disorder can promote superfluidity and providing quantitative comparisons with recent experiments.

Contribution

It introduces phase diagrams for disordered Bose gases in 2D and 3D, highlighting the role of disorder in superfluidity and offering a theoretical framework aligned with experimental observations.

Findings

Small disorder enhances superfluidity.

Superfluid transition curves are mapped in disorder-temperature and disorder-entropy planes.

Results align with recent experimental data on 2D disordered ultra-cold gases.

Abstract

We study the superfluid transitions in bidimensional (2D) and tridimensional (3D) disordered and interacting Bose gases. We work in the limit of long-range correlated disorder such that it can be treated in the local density approximation. We present the superfluid transition curves both in the disorder-temperature plane well as in the disorder-entropy plane in 2D and 3D Bose gases. Surprisingly, we find that a small amount of disorder is always favorable to the apparition of a superfluid. Our results offer a quantitative comparison with recent experiments in 2D disordered ultra-cold gases, for which no exact theory exists.