Dynamic hysteresis from bistability in an antiferromagnetic spinor condensate

TL;DR

This paper investigates hysteresis phenomena during quantum phase transitions in a spin-1 Bose-Einstein condensate, revealing rate-dependent behavior and scaling laws explained by Kibble-Zurek theory, with considerations of external trapping effects.

Contribution

It demonstrates the emergence of hysteresis loops in a spinor condensate during phase transitions and explains their behavior using Kibble-Zurek theory, including effects of trap potentials.

Findings

Hysteresis loops appear during quantum phase transitions in the condensate.

Hysteresis behavior is rate-independent at large magnetizations.

Scaling of hysteresis loop area is observed at small magnetizations.

Abstract

We study the emergence of hysteresis during the process of quantum phase transition from an antiferromagnetic to a phase-separated state in a spin-1 Bose Einstein condensate of ultracold atoms. We explicitly demonstrate the appearance of a hysteresis loop with various quench times showing that it is rate-independent for large magnetizations only. In other cases scaling of the hysteresis loop area is observed, which we explain by using the Kibble-Zurek theory in the limit of small magnetization. The effect of an external harmonic trapping potential is also discussed.