Spin-Hall effect: Back to the Beginning on a Higher Level

TL;DR

This paper reviews the history and recent developments of the spin-Hall effect, clarifying controversies and guiding future research directions in spintronics and spin-orbit coupling phenomena.

Contribution

It provides a comprehensive summary that clarifies settled issues and refocuses research efforts on the spin-Hall effect's fundamental mechanisms.

Findings

Clarified the intrinsic vs. extrinsic origins of the spin-Hall effect

Resolved key controversies from recent debates

Outlined future challenges in spin-Hall research

Abstract

The phenomena of the spin-Hall effect, initially proposed over three decades ago in the context of asymmetric Mott skew scattering, was revived recently by the proposal of a possible intrinsic spin-Hall effect originating from a strongly spin-orbit coupled band structure. This new proposal has generated an extensive debate and controversy over the past two years. The purpose of this workshop, held at the Asian Pacific Center for Theoretical Physics, was to bring together many of the leading groups in this field to resolve such issues and identify future challenges. We offer this short summary to clarify the now settled issues on some of the more controversial aspects of the debate and help refocus the research efforts in new and important avenues.