Quantum gas mixtures in different correlation regimes

TL;DR

This paper develops a many-body theoretical framework for two-component ultracold bosonic gases with different interaction regimes, including a hybrid system with a Tonks-Girardeau gas immersed in a BEC, analyzing phase separation and quantum correlations.

Contribution

It introduces a comprehensive description of mixed quantum gases with varying interaction strengths, including a novel hybrid system in one dimension.

Findings

Quantum correlations persist in phase-separated regimes.

Hybrid systems exhibit tunable superfluid environments.

Microscopic and semiclassical descriptions of phase separation are consistent.

Abstract

We present a many-body description for two-component ultracold bosonic gases when one of the species is in the weakly interacting regime and the other is either weakly or strongly interacting. In the one-dimensional limit the latter case system is a hybrid in which a Tonks-Girardeau gas is immersed in a Bose-Einstein condensate, which is an example of a new class of quantum system involving a tunable, superfluid environment. We describe the process of phase separation microscopically and semiclassically in both situations and show that the quantum correlations are maintained in the separated phase.