Observation of Weak Collapse in a Bose-Einstein Condensate

TL;DR

This paper experimentally investigates the collapse dynamics of an attractive Bose-Einstein condensate, revealing universal behaviour and the counterintuitive weak collapse phenomenon where increased instability leads to less particle loss.

Contribution

It provides the first experimental observation and characterization of weak collapse in a Bose-Einstein condensate, including scaling laws for atom loss.

Findings

Observation of universal collapse behaviour

Experimental signature of weak collapse

Scaling laws for atom loss

Abstract

We study the collapse of an attractive atomic Bose-Einstein condensate prepared in the uniform potential of an optical-box trap. We characterise the critical point for collapse and the collapse dynamics, observing universal behaviour in agreement with theoretical expectations. Most importantly, we observe a clear experimental signature of the counterintuitive weak collapse, namely that making the system more unstable can result in a smaller particle loss. We experimentally determine the scaling laws that govern the weak-collapse atom loss, providing a benchmark for the general theories of nonlinear wave phenomena.