Giant mesoscopic spin Hall effect on surface of topological insulator

TL;DR

This paper analytically investigates the giant mesoscopic spin Hall effect on the surface of topological insulators, revealing oscillating spin polarization induced by electric current that can be observed experimentally.

Contribution

It provides an analytical derivation of the giant spin Hall effect on topological insulator surfaces using the McMillan method in the ballistic limit, highlighting oscillations across potential boundaries.

Findings

Giant spin polarization oscillates across the potential boundary.

Oscillations occur without confinement due to Klein paradox.

Effect should be observable via spin-resolved STM.

Abstract

We study mesoscopic spin Hall effect on the surface of topological insulator with a step-function potential. The giant spin polarization induced by a transverse electric current is derived analytically by using McMillan method in the ballistic transport limit, which oscillates across the potential boundary with no confinement from the potential barrier due to the Klein paradox, and should be observable in spin resolved scanning tunneling microscope.