Disorder Effects in the Quantum Hall Effect of Graphene p-n Junctions

TL;DR

This paper investigates how disorder at the interface of graphene p-n junctions affects the quantum Hall effect, revealing conductance fluctuations and universal behaviors consistent with theoretical models.

Contribution

It provides a numerical analysis of disorder effects on quantum Hall conductance in graphene p-n junctions, connecting experimental observables with theoretical predictions.

Findings

Conductance plateaus depend on disorder strength.

Universal conductance fluctuations observed in the bipolar regime.

Fano factors can identify transport characteristics.

Abstract

The quantum Hall effect in graphene p-n junctions is studied numerically with emphasis on the effect of disorder at the interface of two adjacent regions. Conductance plateaus are found to be attached to the intensity of the disorder, and are accompanied by universal conductance fluctuations in the bipolar regime, which is in good agreement with theoretical predictions of the random matrix theory on quantum chaotic cavities. The calculated Fano factors can be used in an experimental identification of the underlying transport character.