Dynamics of a few interacting bosons escaping from an open well

TL;DR

This paper investigates how a small number of ultra-cold bosons escape from a one-dimensional well, revealing interaction-dependent transitions between different decay mechanisms that influence the decay rate, with implications for experimental observation.

Contribution

It introduces a theoretical framework to understand decay channel transitions in few-boson systems as interaction strength varies.

Findings

Decay rate changes at transition points

Different decay channels dominate in different regimes

Transitions occur when new decay channels become energetically accessible

Abstract

The dynamics of a few ultra-cold bosons tunneling from a one-dimensional potential well into open space is studied. In such a system several decay channels can be distinguished, each corresponding to a different number of bosons escaping simultaneously. We show that as the interparticle interaction strength is changed, the system undergoes transitions between distinct regimes characterized by the dominance of different decay channels. These transitions are reflected in the behavior of the decay rate of the system, which is measurable experimentally. By means of a simple theoretical description we show that the transitions occur at the points where a new decay channel becomes energetically viable. The results provide insight into the behavior of decaying few-body systems and may have potential interest to experiments.