Metastable phase in the quantum Hall ferromagnet

TL;DR

This paper investigates a metastable phase in a quantum Hall ferromagnet, revealing non-equilibrium dynamics and magnetic domain behavior influenced by gate voltage and temperature.

Contribution

It uncovers a metastable phase with unique relaxation dynamics and domain behavior in quantum Hall ferromagnets, advancing understanding of non-equilibrium phenomena in these systems.

Findings

Metastable phase appears near Landau level degeneracy

Relaxation follows a stretched exponential behavior

Hysteresis loops relate to magnetic domain dynamics

Abstract

Time-dependent capacitance measurements reveal an unstable phase of electrons in gallium arsenide quantum well that occurs when two Landau levels with opposite spin are brought close to degeneracy by applying a gate voltage. This phase emerges below a critical temperature and displays a peculiar non-equilibrium dynamical evolution. The relaxation dynamics is found to follow a stretched exponential behavior and correlates with hysteresis loops observed by sweeping the magnetic field. These experiments indicate that metastable randomly-distributed magnetic domains are involved in the relaxation process in a way that is equivalently tunable by a change in gate voltage or temperature.