Anisotropic universal conductance fluctuations in disordered quantum wires with Rashba and Dresselhaus spin-orbit interaction and applied in-plane magnetic field

TL;DR

This paper studies how the conductance fluctuations in disordered quantum wires with spin-orbit interactions and magnetic fields depend on the magnetic field direction, revealing anisotropic behavior linked to underlying symmetries.

Contribution

It demonstrates that universal conductance fluctuations exhibit anisotropy due to spin-orbit interactions and magnetic field orientation, enabling electrical detection of interaction ratios.

Findings

Conductance fluctuations are anisotropic with magnetic field direction.

Anisotropy can be explained by Hamiltonian symmetries.

Electrical measurements can determine Rashba and Dresselhaus ratio.

Abstract

We investigate the transport properties of narrow quantum wires realized in disordered two-dimensional electron gases in the presence of k-linear Rashba and Dresselhaus spin-orbit interaction (SOI), and an applied in-plane magnetic field. Building on previous work [Scheid, et al., PRL 101, 266401 (2008)], we find that in addition to the conductance, the universal conductance fluctuations also feature anisotropy with respect to the magnetic field direction. This anisotropy can be explained solely from the symmetries exhibited by the Hamiltonian as well as the relative strengths of the Rashba and Dresselhaus spin orbit interaction and thus can be utilized to detect this ratio from purely electrical measurements.