Spin Filter Effects in Mesoscopic Ring Structures

TL;DR

This paper investigates how mesoscopic ring structures with inhomogeneous magnetic fields can generate and control spin-polarized currents, demonstrating potential for spintronic device applications.

Contribution

It introduces a novel device design using two connected rings to create and control spin-polarized currents via a spin-switch effect.

Findings

Small Zeeman splitting induces significant spin polarization.

Proposed device can coherently control spin currents at low temperatures.

Spin-filter effects are achievable in mesoscopic ring structures.

Abstract

We study the spin-dependent conductance of ballistic mesoscopic ring systems in the presence of an inhomogeneous magnetic field. We show that, for the setup proposed, even a small Zeeman splitting can lead to a considerable spin polarisation of the current. Making use of a spin-switch effect predicted for such systems we propose a device of two rings connected in series that in principle allows for both creating and coherently controlling spin polarized currents at low temperatures.