Spin separation in a T ballistic nanojunction due to lateral-confinement-induced spin-orbit-coupling

TL;DR

This paper introduces a novel spin filtering method in ballistic nanostructures using lateral-confinement-induced spin-orbit coupling, enabling spin polarization detection and generation in 2DEGs.

Contribution

It presents a new scheme leveraging lateral electric fields for spin filtering, differing from traditional approaches based on confinement-induced spin-orbit effects.

Findings

The proposed device can generate spin-polarized currents.

It allows electric measurement of spin polarization.

Numerical results confirm effective spin filtering in single-channel transport.

Abstract

We propose a new scheme of spin filtering employing ballistic nanostructures in two dimensional electron gases (2DEGs). The proposal is essentially based on the spin-orbit (SO) interaction arising from the lateral confining electric field. This sets the basic difference with other works employing ballistic crosses and T junctions with the conventional SO term arising from 2DEG confinement. We discuss the consequences of this different approach on magnetotransport properties of the device, showing that the filter can in principle be used not only to generate a spin polarized current but also to perform an electric measurement of the spin polarization of a charge current. We focus on single-channel transport and investigate numerically the spin polarization of the current.