Interference and transport properties of conductions electrons on the surface of a topological insulator

TL;DR

This paper investigates the surface conductivity of conduction electrons with fixed chirality in topological insulators, revealing anti-localization effects due to correlated noise and comparing theoretical results with experimental Raman measurements.

Contribution

It models surface electrons in topological insulators as spinless particles with fixed chirality, incorporating vortex effects and analyzing conductivity behavior.

Findings

Conductivity exhibits anti-localization due to correlated noise.

Theoretical results align with Raman shift measurements for Bi₂Se₃.

Surface electrons behave as spinless particles with vortex-induced effects.

Abstract

The surface conductivity for conduction electrons with a fixed chirality in a topological insulator with impurities scattering is considered. The surface excitations are described by the Weyl Hamiltonian. For a finite chemical potential one projects out the hole band and one obtains a single electronic band with a fixed chirality. One obtains a model of spinless electrons which experience a half vortex when they return to the origin. As a result the conductivity is equivalent to a spinless problem with correlated noise which gives rise to anti-localization. We compute conductivity as a function of frequency and compare our results with the $Raman$ shift measurement for $Bi_{2}Se_{3}$.