Experimental Observation of the Inverse Spin Hall Effect at Room Temperature

TL;DR

This paper reports the first room-temperature observation of the inverse spin Hall effect in a two-dimensional electron gas, demonstrating its robustness and potential for spintronic applications.

Contribution

It provides experimental evidence of the inverse spin Hall effect at room temperature in macroscopic samples, with quantitative measurement of spin Hall conductivity.

Findings

Inverse spin Hall effect observed at room temperature

Spin Hall conductivity around 0.5(e^2/h)

Effect is robust in macroscopic samples

Abstract

We observe the inverse spin Hall effect in a two-dimensional electron gas confined in AlGaAs/InGaAs quantum wells. Specifically, we find that an inhomogeneous spin density induced by the optical injection gives rise an electric current transverse to both the spin polarization and its gradient. The spin Hall conductivity can be inferred from such a measurement through the Einstein relation and the Onsager relation, and is found to have the order of magnitude of $0.5(e^{2}/h)$. The observation is made at the room temperature and in samples with macroscopic sizes, suggesting that the inverse spin Hall effect is a robust macroscopic transport phenomenon.