Response of a spin valve to a spin battery

TL;DR

This paper demonstrates that spin valves can act as perfect spin transistors, exhibiting an ON-OFF response to spin batteries and enabling infinite magnetoresistance with pure spin currents.

Contribution

It introduces the concept that spin valves can serve as perfect spin transistors with an ON-OFF response to spin batteries under symmetry conditions.

Findings

Spin valves exhibit ON-OFF response to spin batteries.

Pure spin currents can generate infinite magnetoresistance.

Magnetic tunnel junctions and metallic trilayers are analyzed.

Abstract

It is shown that spin valves under suitable symmetry conditions exhibit an ON-OFF response to a spin battery, and are therefore perfect spin transistors. While a spin valve driven by a charge battery displays the usual GMR (Giant Magneto-Resistance), this means that a pure spin current or pure spin accumulation can generate an infinite magnetoresistance (IMR). Magnetic tunnel junctions as well as CPP (current perpendicular to plane) or CIP (current in plane) metallic trilayers are discussed.