Spintronics with NSN Junction of one-dimensional quantum wires : A study of Pure Spin Current and Magnetoresistance

TL;DR

This paper explores how one-dimensional quantum wire NSN junctions can generate pure spin currents and exhibit large tunnelling magnetoresistance, analyzing electron interactions and fixed points relevant for spintronics applications.

Contribution

It identifies fixed points leading to pure spin current and examines the impact of electron-electron interactions on their stability in quantum wire NSN junctions.

Findings

Fixed points correspond to pure spin current production.

Electron interactions influence the stability of pure spin currents.

Temperature dependence of magnetoresistance follows a power law.

Abstract

We demonstrate possible scenarios for production of pure spin current and large tunnelling magnetoresistance ratios from elastic co-tunnelling and crossed Andreev reflection across a superconducting junction comprising of normal metal-superconductor-normal metal, where, the normal metal is a one-dimensional interacting quantum wire. We show that there are fixed points in the theory which correspond to the case of pure spin current. We analyze the influence of electron-electron interaction and see how it stabilizes or de-stabilizes the production of pure spin current. These fixed points can be of direct experimental relevance for spintronics application of normal metal-superconductor-normal metal junctions of one-dimensional quantum wires. We also calculate the power law temperature dependence of the crossed Andreev reflection enhanced tunnelling magnetoresistance ratio for the normal metal-superconductor-normal metal junction.