Two-phonon scattering in graphene in the quantum Hall regime

TL;DR

This paper investigates how two-phonon scattering affects the longitudinal conductivity in graphene under quantum Hall conditions, revealing that phonon effects are significant compared to disorder in this regime.

Contribution

It provides the first calculation of two-phonon scattering contributions to conductivity in graphene within the quantum Hall regime.

Findings

Two-phonon scattering becomes comparable to disorder-induced conductivity in graphene.

Phonon effects are negligible in conventional semiconductors but significant in graphene.

The study highlights the importance of phonon interactions at elevated temperatures in quantum Hall graphene.

Abstract

One of the most distinctive features of graphene is its huge inter-Landau-level splitting in experimentally attainable magnetic fields which results in the room-temperature quantum Hall effect. In this paper we calculate the longitudinal conductivity induced by two-phonon scattering in graphene in a quantizing magnetic field at elevated temperatures. It is concluded that the purely phonon-induced scattering, negligible for conventional semiconductor heterostructures under quantum Hall conditions, becomes comparable to the disorder-induced contribution to the dissipative conductivity of graphene in the quantum Hall regime.