Disordered Quantum smectics

TL;DR

This paper investigates how disorder affects the quantum Hall smectic phase in 2D electron systems, revealing anisotropic pinning behavior and a wavelength-dependent conductivity peak.

Contribution

It introduces a Gaussian Variational approach to analyze impurity pinning in quantum Hall smectics, highlighting anisotropic density correlations and dynamical conductivity features.

Findings

Density correlations show quasi long-range order along stripes.

Transverse correlations are infra red divergent.

Dynamical conductivity exhibits a wavelength-dependent pinning peak.

Abstract

We study the impurity pinning of the Quantum Hall (QH) smectic state arising in two dimensional electron systems in high Landau levels. We use replicas and a Gaussian Variational method to deal with the disorder. The pinned quantum smectic exhibits very anisotropic behaviour, with density correlations along the direction of the stripes manifesting a Bragg-Glass type behaviour i.e., quasi long range order whereas those in the transverse direction are infra red divergent. We calculate the dynamical conductivity along the stripe direction and find a wavelength dependent pinning peak.