Generation and control of noncollinear magnetism by supercurrent

TL;DR

This paper demonstrates how supercurrents can induce and control noncollinear magnetic orders in a correlated metal on a superconductor, enabling tunable magnetic textures via supercurrent direction.

Contribution

It introduces a method to generate and manipulate noncollinear magnetism using supercurrents, with potential applications in superconducting spintronics.

Findings

Supercurrents enhance magnetic instability in correlated metals.

Phase transitions to noncollinear magnetic states are induced by supercurrents.

Magnetic textures can be switched by changing supercurrent direction.

Abstract

When superconductivity couples with noncollinear spin textures, rich physics arises; for instance, singlet Cooper pairs can be converted to triplet pairs, and topological superconductors can be realized. For their applications, the controllability of noncollinear magnetism is a crucial issue. Here, we propose that a supercurrent can induce and control noncollinear magnetic orders in a correlated metal on top of a singlet superconductor. We show that the magnetic instability in the correlated metal is enhanced by the proximity effect of supercurrents, which leads to phase transitions from a paramagnetic state to noncollinear magnetic phases with helical or vortexlike spin textures. Furthermore, these magnetic orders can be switched by the direction of the supercurrent. We also discuss the effect of the Rashba spin-orbit coupling and the experimental realization.