New Anisotropic Behavior of Quantum Hall Resistance in (110) GaAs Heterostructures at mK Temperatures and Fractional Filling Factors

TL;DR

This study reports novel anisotropic behaviors in quantum Hall resistance in (110) GaAs heterostructures at millikelvin temperatures, revealing new transport anisotropies within the lowest Landau-Level that depend on magnetic field polarity.

Contribution

It presents the first observation of transport anisotropies within the lowest Landau-Level in (110) GaAs heterostructures, expanding understanding of quantum Hall effects.

Findings

Transport anisotropy observed at higher Landau-Levels.

First detection of anisotropies within the lowest Landau-Level.

Anisotropy depends on magnetic field polarity.

Abstract

Transport experiments in high mobility (110) GaAs heterostructures have been performed at very low temperatures 8 mK. At higher Landau-Levels we observe a transport anisotropy that bears some similarity with what is already seen at half-odd-integer filling on (001) oriented substrates. In addition we report the first observation of transport anisotropies within the lowest Landau-Level. This remarkable new anisotropy is independent of the current direction and depends on the polarity of the magnetic field.