Anisotropic States of Two-Dimensional Electron Systems in High Landau Levels: Effect of an In-Plane Magnetic Field

TL;DR

This paper investigates how an in-plane magnetic field influences the anisotropic resistivity of two-dimensional electron systems in high Landau levels, revealing significant directional changes and destruction of quantum Hall states.

Contribution

It demonstrates the sensitivity of anisotropic resistivity to in-plane magnetic fields and uncovers the interchange of transport directions in high Landau levels.

Findings

In-plane magnetic field causes interchange of 'hard' and 'easy' transport directions.

Large in-plane field destroys isotropic resistivity and quantum Hall state at nu=5/2.

Transport becomes highly anisotropic under strong in-plane magnetic fields.

Abstract

We report the observation of an acute sensitivity of the anisotropic longitudinal resistivity of two-dimensional electron systems in half-filled high Landau levels to the magnitude and orientation of an in-plane magnetic field. In the third and higher Landau levels, at filling fractions nu=9/2, 11/2, etc., the in-plane field can lead to a striking interchange of the "hard" and "easy" transport directions. In the second Landau level the normally isotropic resistivity and the weak nu=5/2 quantized Hall state are destroyed by a large in-plane field and the transport becomes highly anisotropic.