Chiral pair density wave states generated by spin supercurrents

TL;DR

This paper demonstrates that spin supercurrents can induce chiral pair density wave states in magnetic superconductors, revealing a new mechanism for inhomogeneous parity-breaking ground states involving chiral magnetic and pair density wave orders.

Contribution

It introduces a novel mechanism where spin supercurrents generate Dzyaloshinskii-Moriya interactions, leading to inhomogeneous chiral states in superconducting systems.

Findings

Spin supercurrents induce Dzyaloshinskii-Moriya interactions proportional to the superconducting order.

Inhomogeneous parity-breaking states combining chiral magnetic helix and pair density wave orders are predicted.

Re-entrant transitions into these states occur with decreasing temperature.

Abstract

We report that spin supercurrents in magnetic superconductors and superconductor/ferromagnetic insulator bilayers can induce the Dzyaloshinskii-Moriya interaction which strength is proportional to the superconducting order parameter amplitude. This effect leads to the existence of inhomogeneous parity-breaking ground states combining the chiral magnetic helix and the pair density wave orders. The formation of such states takes place via the penetration of chiral domain walls at the threshold temperature below the superconducting transition. We find regimes with both the single and the re-entrant transitions into the inhomogeneous states with decreasing temperature. The predicted hybrid chiral states can be found in the existing structures with realistic parameters and materials combinations.