Layer charge instability in unbalanced bilayer systems in the quantum Hall regime

TL;DR

This study investigates charge distribution instabilities in unbalanced GaAs bilayer systems under quantum Hall conditions, revealing hysteresis and time-dependent resistance anomalies linked to Landau level filling factors.

Contribution

It uncovers magneto-resistance hysteresis and time-dependent resistance jumps caused by charge instabilities in unbalanced bilayer quantum Hall systems.

Findings

Hysteresis observed at Landau level filling factor one

Resistance exhibits random jumps and slow relaxations

Charge distribution instabilities cause observed anomalies

Abstract

Measurements in GaAs hole bilayers with unequal layer densities reveal a pronounced magneto-resistance hysteresis at the magnetic field positions where either the majority or minority layer is at Landau level filling factor one. At a fixed field in the hysteretic regions, the resistance exhibits an unusual time dependence, consisting of random, bidirectional jumps followed by slow relaxations. These anomalies are apparently caused by instabilities in the charge distribution of the two layers.