Current-induced asymmetries of incompressible stripes in narrow quantum Hall systems

TL;DR

This paper experimentally confirms and theoretically explains the asymmetries in current distribution in narrow quantum Hall systems under strong magnetic fields, highlighting the role of non-linear feedback effects and parameters like current strength and temperature.

Contribution

It combines experimental validation with a self-consistent theoretical model to elucidate current asymmetries in quantum Hall systems, advancing understanding of IQHE breakdown mechanisms.

Findings

Confirmed strong asymmetries in current distribution experimentally.

Theoretical model explains many experimental observations.

Identified conditions where IQHE breakdown mechanisms are significant.

Abstract

We present recent experimental results confirming previously predicted strong asymmetries of the current distribution in narrow Hall bars under the conditions of the integer quantum Hall effect (IQHE). Using a previously developed self-consistent screening and transport theory of the IQHE, we investigate how these asymmetries, which are due to a non-linear feedback effect of the imposed current on the electron distribution in the sample, depend on relevant parameters, such as the strength of the imposed current, the magnetic field, the temperature, and the collision broadening of the Landau-quantized energy bands. We find that many aspects of the experimental results can be understood within this approach, whereas other aspects require explicit consideration of mechanism, which enforce the breakdown of the IQHE.