Origin and control of spin currents in a magnetic triplet Josephson junction

TL;DR

This paper investigates how spin currents arise and can be controlled in a triplet superconductor Josephson junction with a magnetic barrier, revealing three mechanisms and their symmetry properties.

Contribution

It identifies three distinct mechanisms for generating spin currents and demonstrates how to control them independently in a triplet Josephson junction.

Findings

Three mechanisms produce spin currents in the junction.

Spin currents can be independently controlled on either side.

Symmetry analysis explains the physical origins of each mechanism.

Abstract

We study the appearance of a Josephson spin current in a model triplet superconductor junction with a magnetically-active tunnelling barrier. We find three distinct mechanisms for producing a spin current, and we provide a detailed discussion of the symmetry properties and the physical origins of each. By combining these three basic mechanisms, we find that it is possible to exercise fine control over the spin currents. In particular, we show that unlike the charge current, the spin currents on either side of the barrier need not be identical.