Comment on Theory of spin Hall effect

TL;DR

This paper highlights that a previously proposed mechanism for the intrinsic spin Hall effect, based on an extension of the Drude model, was independently developed earlier, supporting its physical validity across various materials.

Contribution

It demonstrates that an alternative treatment of the spin Hall effect proposed earlier aligns with recent models, reinforcing the mechanism's broad applicability.

Findings

Independent proposals confirm the mechanism's validity

Applicable to all metals and semiconductors

Supports understanding of anomalous Hall effect

Abstract

Chudnovsky recently proposed (arXiv: 0709.0725) a beautifully simple mechanism for the intrinsic spin Hall effect involving an extension of the Drude model. We point out that an equivalent proposal was made by us in an alternative treatment of the problem in Phys.Rev. B60, 14787 (1999) (arXiv:cond-mat/9910408, reaching identical conclusions. The coincidence of both approaches supports their physical validity. The mechanism applies to the spin Hall effect in all metals and semiconductors and to the anomalous Hall effect in all ferromagnetic metals and semiconductors.