# Anomalous currents and spontaneous vortices in spin-orbit coupled superconductors

## TL;DR

This paper proposes a new mechanism for generating supercurrents and vortices in superconductors with magnetic inclusions using spin-orbit coupling.

## Contribution

The novelty lies in using spin-orbit coupling and magnetic inclusions to generate spontaneous vortices without an external magnetic field.

## Key findings

- Spin-orbit coupling creates an effective gauge field that influences Cooper pairs near magnetic inclusions.
- The mechanism can either enhance or reduce magnetization depending on material parameters.
- Spontaneous vortices can form in superconductors with the right inclusion distribution.

## Abstract

We propose a mechanism which can generate supercurrents in spin-orbit coupled superconductors with charged magnetic inclusions. The basic idea is that through spin-orbit interaction, the in-plane electric field near the edge of each inclusion appears to the electrons as an effective spin-dependent gauge field; if Cooper pairs can be partially spin polarized, then each pair experiences a nonzero net transverse pseudo-gauge field. We explore the phenomenology of our mechanism within a Ginzburg-Landau theory, with parameters determined from a microscopic model. Depending on parameters, our mechanism can either enhance or reduce the total magnetization upon superconducting condensation. Given an appropriate distribution of inclusions, we show how our mechanism can generate superconducting vortices without any applied orbital magnetic field. Our mechanism can produce similar qualitative behavior to the “magnetic memory effect” observed in 4Hb-TaS21. However, the magnitude of the effect in that material seems larger than our model can naturally explain.