Superconducting double spin valve with extraordinary large tunable magnetoresistance

TL;DR

This paper proposes a superconducting double spin valve that leverages spin-filtering and nonequilibrium effects to achieve extremely large, tunable magnetoresistance, promising for low-temperature technologies.

Contribution

It introduces a novel superconducting spin valve device with tunable, giant magnetoresistance based on interplay between spin-filtering and nonequilibrium transport effects.

Findings

Magnetoresistance can reach 10^2 to 10^6% with realistic materials.

Magnetoresistance is tunable over several orders of magnitude.

Device operation is suitable for low-temperature applications.

Abstract

A superconducting double spin valve device is proposed. Its operation takes advantage of the interplay between the spin-filtering effect of ferromagnetic insulators and superconductivity-induced out-of-equilibrium transport. Depending on the degree of nonequilibrium, extraordinary large tunnel magnetoresistance as large as 10^2...10^6% can be obtained for realistic material parameters, and it can be tuned over several orders of magnitude under proper voltage biasing and temperature. The relevance of this setup for low-temperature applications is further discussed.