Interaction-Induced Localization of an Impurity in a Trapped Bose Condensate

TL;DR

This paper investigates how an impurity's localization in a trapped Bose condensate affects the condensate's properties, revealing controllable impurity localization and potential instability leading to collapse, with implications for experimental observation.

Contribution

It introduces a method to control impurity localization in a Bose condensate and explores the resulting effects on condensate stability and density profiles.

Findings

Impurity localization increases with attractive interaction strength.

Localized impurity enhances condensate density at the trap center.

Strong attraction can destabilize the condensate, causing collapse.

Abstract

We study the ground state properties of a trapped Bose condensate with a neutral impurity. By varying the strength of the attractive atom-impurity interactions the degree of localization of the impurity at the trap center can be controlled. As the impurity becomes more strongly localized the peak condensate density, which can be monitored experimentally, grows markedly. For strong enough attraction, the impurity can make the condensate unstable by strongly deforming the atom density in the neighborhood of the impurity. This "collapse" can possibly be investigated in bosenova-type experiments.