Imaging of Low Compressibility Strips in the Quantum Hall Liquid

TL;DR

This paper uses advanced microscopy to image low compressibility strips in the quantum Hall liquid, revealing wider-than-expected features and proposing a disorder-based model to explain the discrepancy.

Contribution

It provides the first detailed imaging of low compressibility strips at specific quantum Hall filling factors and introduces a model considering disorder effects.

Findings

Imaged low compressibility strips at filling factors ν=2 and 4.

Observed strips are wider than theoretical predictions.

Proposed a disorder-induced density of states model to explain the discrepancy.

Abstract

Using Subsurface Charge Accumulation scanning microscopy we image strips of low compressibility corresponding to several integer Quantum Hall filling factors. We study in detail the strips at Landau level filling factors $\nu =$ 2 and 4. The observed strips appear significantly wider than predicted by theory. We present a model accounting for the discrepancy by considering a disorder-induced nonzero density of states in the cyclotron gap.