Quantum interference in HgTe structures

TL;DR

This paper investigates quantum interference effects in HgTe/HgCdTe quantum wells, analyzing symmetry properties, symmetry-breaking patterns, and their impact on conductivity corrections and magnetoresistance in various geometries.

Contribution

It provides a comprehensive analysis of symmetry-breaking effects on quantum interference in HgTe structures, including microscopic calculations beyond the diffusion approximation.

Findings

Symmetry properties influence weak localization and antilocalization behaviors.

Quantum corrections to conductivity depend on symmetry-breaking perturbations.

Magnetoresistance patterns are characterized in quasi-one-dimensional geometries.

Abstract

We study quantum transport in HgTe/HgCdTe quantum wells under the condition that the chemical potential is located outside of the bandgap. We first analyze symmetry properties of the effective Bernevig-Hughes-Zhang Hamiltonian and the relevant symmetry-breaking perturbations. Based on this analysis, we overview possible patterns of symmetry breaking that govern the quantum interference (weak localization or weak antilocalization) correction to the conductivity in two dimensional HgTe/HgCdTe samples. Further, we perform a microscopic calculation of the quantum correction beyond the diffusion approximation. Finally, the interference correction and the low-field magnetoresistance in a quasi-one-dimensional geometry are analyzed.