Bubble nucleation in a cold spin 1 gas

TL;DR

This paper investigates bubble nucleation during a first order phase transition in a cold spin-1 atomic gas, using theoretical models and simulations to understand nucleation rates and spatial distribution.

Contribution

It introduces a three-level system model for bubble nucleation in a cold atomic gas and compares different methods to calculate nucleation rates.

Findings

Good agreement between stochastic and instanton methods for nucleation rates

Bubbles tend to nucleate near the trap walls in optical box traps

Nucleation occurs in two dimensions at non-zero temperature

Abstract

Cold atomic gases offer the prospect of simulating the physics of the very early universe in the laboratory. In the condensate phase, the gas is described by a field theory with key features of high energy particle theory. This paper describes a three level system which undergoes a first order phase transition through the nucleation of bubbles. The theoretical investigation shows bubbles nucleating in two dimensions at non-zero temperature. There is good agreement between the bubble nucleation rates calculated from a Stochastic Projected Gross-Pitaevskii equation and from a non-perturbative instanton method. When an optical box trap is included in the simulations, the bubbles nucleate preferentially near the walls of the trap.