Spatial separation of spin currents in transition metal dichalcogenides

TL;DR

This paper theoretically demonstrates that transition metal dichalcogenides can spatially separate spin-polarized currents due to trigonal warping, with potential applications in spintronics and spin discrimination.

Contribution

It introduces a theoretical prediction of spin current separation in TMDs based on trigonal warping effects, including analysis of disorder impacts.

Findings

Spin-polarized currents can be spatially separated in TMDs.

The spin polarization depends on carrier energy and crystallographic direction.

Disorder negatively affects the observed spin polarization.

Abstract

We theoretically predict spatial separation of spin-polarized ballistic currents in transition metal dichalcogenides (TMDs) due to trigonal warping. We quantify the effect in terms of spin polarization of charge carrier currents in a prototypical 3-terminal ballistic device where spin-up and spin-down charge carriers are collected by different leads. We show that the magnitude of the current spin polarization depends strongly on the charge carrier energy and the direction with respect to crystallographic orientations in the device. We study the (negative) effect of lattice imperfections and disorder on the observed spin polarization. Our investigation provides an avenue towards observing spin discrimination in a defect-free time reversal-invariant material.