Magnetoresistance of edge states of a two-dimensional topological insulator

TL;DR

This paper develops a theoretical model for the magnetoresistance in edge states of 2D topological insulators, highlighting how magnetic fields and impurities influence electron backscattering and resistance.

Contribution

It introduces a new theoretical framework explaining how magnetic fields and impurities affect edge state magnetoresistance in 2D topological insulators.

Findings

Magnetic field opens an energy gap in edge states.

Impurities enable backscattering, increasing resistance.

Strong impurity interactions suppress backscattering.

Abstract

The theory of magnetoresistance of the edge state of a two-dimensional topological insulator is developed. The magnetic field violates the time-reversal invariance. Magnetoresistance arises due to the energy gap opened by a magnetic field parallel to the sample surface. The combined action of impurities and the magnetic field causes backscattering of edge electrons. Although impurities are necessary for scattering, sufficiently strong interaction with impurities leads to the suppression of backscattering.