Measurement of spin-dependent conductivities in a two-dimensional electron gas

TL;DR

This paper measures spin-dependent conductivities in a GaAs 2D electron gas by generating and detecting spin accumulation through a non-local geometry, revealing enhanced electron spin susceptibility.

Contribution

It introduces a method to measure spin accumulation from bulk conductivity differences without spin-polarized nanostructures, highlighting enhanced spin susceptibility.

Findings

Spin accumulation is generated by unpolarized current in 2D electron gas.

Comparison with a diffusive model indicates enhanced spin susceptibility.

Measurement technique differs from previous nanostructure-based methods.

Abstract

Spin accumulation is generated by injecting an unpolarized charge current into a channel of GaAs two-dimensional electron gas subject to an in-plane magnetic field, then measured in a non-local geometry. Unlike previous measurements that have used spin-polarized nanostructures, here the spin accumulation arises simply from the difference in bulk conductivities for spin-up and spin-down carriers. Comparison to a diffusive model that includes spin subband splitting in magnetic field suggests a significantly enhanced electron spin susceptibility in the 2D electron gas.