Highly Polarized and Long Range Dissipationless Spin Transport Due to Counterflowing Electron and Hole Edge Channels

TL;DR

This paper theoretically demonstrates that in graphene interfaced with a magnetic material, counterflowing spin-polarized edge channels enable dissipationless spin transport over long distances, surpassing 100% spin polarization, even without charge current.

Contribution

It introduces a novel mechanism for dissipationless spin transport via counterflowing edge channels with spin-flip scattering in magnetic graphene.

Findings

Achieves over 100% spin polarization in charge current.

Enables long-range spin transport without charge current.

Provides a theoretical framework for spin transport in magnetic graphene.

Abstract

The presence of edge channels in the quantum Hall regime leads to dissipationless charge transport over long distances. When graphene is interfaced with a magnetic material, the exchange interaction lifts the Landau levels spin degeneracy. This causes the presence of counterflowing edge channels with opposite spin polarization. We show theoretically that the spin-flip scattering between these edge channels enables a dissipationless spin transport with larger than 100% spin polarization of the charge current. It also allows the transport of spin over macroscopically long distances, even in the absence of an applied charge current.