Dynamics of a quenched spin-1 antiferromagnetic condensate in a harmonic trap

TL;DR

This paper models the dynamics of a quenched spin-1 antiferromagnetic condensate in a harmonic trap, showing agreement with experiments and exploring early universal phase ordering with domain growth analysis.

Contribution

It introduces a classical field simulation approach to replicate experimental quenched condensate dynamics and analyzes early phase ordering using a developed nematic order parameter.

Findings

Good agreement with experimental observations

Identification of diffusive domain growth in early phase ordering

Development of a nematic order parameter for analysis

Abstract

In this paper we consider a recent experiment [Kang et al. PRA 95 053638 (2017)] in which an antiferromagnetic spin-1 condensate of 23Na atoms was quenched from the easy-axis polar phase into the easy-plane polar phase. We simulate the phase transition dynamics using a classical field method with noisy initial conditions and find good agreement to the experimental observations. We analyse the late-time dynamics in terms of phase ordering using the nematic order parameter that we have developed in earlier work [Symes et al. PRA 96, 013602 (2017)]. We show that these experiments are able to explore the early stages of universal phase ordering where the domains grow diffusively.