Spin orbit-induced anisotropic conductivity of a disordered 2DEG

TL;DR

This paper introduces a semi-automated method to compute diagrammatic disorder averaging in 2D conductors with spin-orbit interaction, revealing anisotropic conductivity effects influenced by Rashba and Dresselhaus SOI.

Contribution

A new semi-automated computational approach for diagram calculations in disordered 2D systems with spin-orbit coupling, analyzing anisotropic conductivity effects.

Findings

Anisotropic conductivity corrections due to SOI in 2D systems.

Enhanced anisotropy in quasi-1D geometries with SOI.

Breaking time-reversal symmetry increases conductivity anisotropy.

Abstract

We present a semi-automated computer-assisted method to generate and calculate diagrams in the disorder averaging approach to disordered 2D conductors with intrinsic spin-orbit interaction (SOI). As an application, we calculate the effect of the SOI on the charge conductivity for disordered 2D systems and rings in the presence of Rashba and Dresselhaus SOI. In an infinite-size 2D system, anisotropic corrections to the conductivity tensor arise due to phase-coherence and the interplay of Rashba and Dresselhaus SOI. The effect is more pronounced in the quasi-onedimensional case, where the conductivity becomes anisotropic already in the presence of only one type of SOI. The anisotropy further increases if the time-reversal symmetry of the Hamiltonian is broken.