Low-Temperature Conductivity of Weakly Interacting Quantum Spin Hall Edges in Strained-Layer InAs/GaInSb

TL;DR

This study investigates the low-temperature electrical conductance of helical edge states in strained InAs/GaInSb quantum wells, revealing weak interactions and the influence of disorder and magnetic fields on these topologically protected states.

Contribution

It provides experimental evidence of weakly interacting helical edge states in InAs/GaInSb quantum wells and analyzes their magnetoresistance behavior.

Findings

Edge conductance aligns with weakly interacting helical edge theory

Magnetoresistance relates to edge interaction and disorder effects

Conductance remains robust at low temperatures

Abstract

We report low-temperature transport measurements in strained InAs/Ga0.68In0.32Sb quantum wells, which supports time-reversal symmetry-protected helical edge states. The temperature and bias voltage dependence of the helical edge conductance for devices of various sizes are consistent with the theoretical expectation of a weakly interacting helical edge state. Moreover, we found that the magnetoresistance of the helical edge states is related to the edge interaction effect and the disorder strength.