Gate-Controlled Spin-Orbit Quantum Interference Effects in Lateral Transport

TL;DR

This paper demonstrates in situ control of spin-orbit coupling in a 2DEG, enabling a gate-tunable transition from weak localization to antilocalization, supported by a developed theory for analyzing magnetotransport data.

Contribution

It introduces a comprehensive theory for 2D magnetotransport with spin-orbit coupling beyond the diffusive limit and applies it to experimental data to quantify different spin-orbit contributions.

Findings

Gate-tunable crossover from weak localization to antilocalization.

Separate estimation of Rashba and Dresselhaus spin-orbit contributions.

Extraction of spin-orbit precession angular dependence at various gate voltages.

Abstract

In situ control of spin-orbit coupling in coherent transport using a clean GaAs/AlGaAs 2DEG is realized, leading to a gate-tunable crossover from weak localization to antilocalization. The necessary theory of 2D magnetotransport in the presence of spin-orbit coupling beyond the diffusive approximation is developed and used to analyze experimental data. With this theory the Rashba contribution and linear and cubic Dresselhaus contributions to spin-orbit coupling are separately estimated, allowing the angular dependence of spin-orbit precession to be extracted at various gate voltages.