Mean-field description of collapsing and exploding Bose-Einstein condensates

TL;DR

This paper uses numerical simulations of the mean-field Gross-Pitaevskii equation to analyze the dynamics of collapsing and exploding Bose-Einstein condensates of rubidium-85, explaining some experimental observations.

Contribution

It demonstrates that mean-field analysis can effectively describe key aspects of condensate collapse and explosion dynamics observed experimentally.

Findings

Mean-field simulations reproduce experimental collapse behavior.

The analysis explains atom ejection during condensate explosion.

Results support the validity of the Gross-Pitaevskii approach for these phenomena.

Abstract

We perform numerical simulation based on the time-dependent mean-field Gross-Pitaevskii equation to understand some aspects of a recent experiment by Donley et al. on the dynamics of collapsing and exploding Bose-Einstein condensates of $^{85}$Rb atoms. They manipulated the atomic interaction by an external magnetic field via a Feshbach resonance, thus changing the repulsive condensate into an attractive one and vice versa. In the actual experiment they changed suddenly the scattering length of atomic interaction from positive to a large negative value on a pre-formed condensate in an axially symmetric trap. Consequently, the condensate collapses and ejects atoms via explosion. We find that the present mean-field analysis can explain some aspects of the dynamics of the collapsing and exploding Bose-Einstein condensates.