Density and Stability in Ultracold Dilute Boson-Fermion Mixtures

TL;DR

This paper uses mean-field theory to analyze density profiles and stability of ultracold dilute 87Rb-40K Bose-Fermi mixtures, emphasizing the role of particle numbers and interspecies interactions in experimental settings.

Contribution

It provides a detailed theoretical analysis of density distributions and stability criteria for Bose-Fermi mixtures, linking experimental observations to interspecies scattering properties.

Findings

Density profiles depend on particle numbers in the Thomas-Fermi limit.

Stability against collapse is strongly influenced by the interspecies s-wave scattering length.

Experimental stability correlates with specific scattering length values.

Abstract

We analyze in detail recent experiments on ultracold dilute 87Rb-40K mixtures in Hamburg and in Florence within a mean-field theory. To this end we determine how the stationary bosonic and fermionic density profiles in this mixture depend in the Thomas-Fermi limit on the respective particle numbers. Furthermore, we investigate how the observed stability of the Bose-Fermi mixture with respect to collapse is crucially related to the value of the interspecies s-wave scattering length.