Anisotropic Transport of Two-Dimensional Holes in High Landau Levels

TL;DR

This study investigates the directional dependence of magnetoresistance in a two-dimensional hole system within GaAs/AlGaAs, revealing significant anisotropy at specific quantum Hall states influenced by charge distribution properties.

Contribution

It provides new insights into the anisotropic transport behavior of 2D holes in high Landau levels, highlighting the roles of density and symmetry.

Findings

Significant anisotropy observed at half-integer filling factors.

Anisotropy depends on hole density.

Anisotropy depends on charge distribution symmetry.

Abstract

Magnetoresistance data taken along $[\bar{2}33]$ and $[01\bar{1}]$ directions in a GaAs/AlGaAs two-dimensional hole sample with van der Pauw geometry exhibit significant anisotropy at half-integer filling factors. The anisotropy appears to depend on both the density and symmetry of the hole charge distribution.