Spin analog of the controlled Josephson charge current

TL;DR

This paper proposes a method to generate and control a spin current across a junction of non-centrosymmetric superconductors, with potential applications in spintronics devices like a Josephson spin switch.

Contribution

It introduces a novel mechanism for controlling Josephson spin currents via the relative orientation of non-centrosymmetric axes in superconductors.

Findings

The Josephson spin current depends on the angle  between the superconductors' axes.

The spin current modulation is proportional to , enabling control.

Potential application in Josephson spin switches.

Abstract

We propose a controlled Josephson spin current across the junction of two non-centrosymmetric superconductors like CePt_3Si. The Josephson spin current arises due to direction dependent tunneling matrix element and different momentum dependent phases of the triplet components of the gap function. Its modulation with the angle \xi between the noncentrosymmetric axes of two superconductors is proportional to \sin \xi. This particular dependence on \xi may find application of the proposed set-up in making a Josephson spin switch.