Metastable Resistance Anisotropy Orientation of Two-Dimensional Electrons in High Landau Levels

TL;DR

This paper investigates how native symmetry-breaking potentials influence the orientation of anisotropic resistive phases in two-dimensional electron systems under high Landau levels, revealing metastable states and relaxation dynamics.

Contribution

It demonstrates that native potentials have two orthogonal minima and shows how external magnetic fields can initialize and observe relaxation between these states.

Findings

Native potentials have two orthogonal minima.

External magnetic fields can control phase orientation.

Metastable states relax over time toward equilibrium.

Abstract

In half-filled high Landau levels, two-dimensional electron systems possess collective phases which exhibit a strongly anisotropic resistivity tensor. A weak, but as yet unknown, rotational symmetry-breaking potential native to the host semiconductor structure is necessary to orient these phases in macroscopic samples. Making use of the known external symmetry-breaking effect of an in-plane magnetic field, we find that the native potential can have two orthogonal local minima. It is possible to initialize the system in the higher minimum and then observe its relaxation toward equilibrium.