Thermally activated local collapse of a flattened dipolar condensate

TL;DR

This paper develops an analytic and stochastic model to understand local collapse phenomena in flattened dipolar condensates, highlighting their significance near roton regimes and implications for experiments.

Contribution

It introduces a new analytic model for energy barriers and a stochastic GPE approach to simulate local collapse at finite temperatures in dipolar condensates.

Findings

Local collapse involves formation of density spikes.

Collapse dynamics are influenced by roton excitations.

Finite temperature simulations confirm the collapse scenario.

Abstract

We consider the metastable dynamics of a flattened dipolar condensate. We develop an analytic model that quantifies the energy barrier to the system undergoing local collapse to form a density spike. We also develop a stochastic Gross-Pitaevskii equation (SGPE) theory for a flatted dipolar condensate, which we use to perform finite temperature simulations verifying the local collapse scenario. We predict that local collapses play a significant role in the regime where rotons are predicted to exist, and will be an important consideration for experiments looking to detect these excitations.