Majorana Zero Modes in Ferromagnetic Wires without Spin-Orbit Coupling

TL;DR

This paper proposes a new method to realize Majorana zero modes in ferromagnetic wires without using spin-orbit coupling, by leveraging proximity effects and magnetic misalignment.

Contribution

It introduces a controllable platform for Majorana modes that does not depend on spin-orbit coupling, using ferromagnetic insulators and supercurrents.

Findings

Majorana zero modes localize at wire edges

The mechanism does not require spin-orbit coupling

Magnetization misalignment enables topological states

Abstract

We present a novel controllable platform for engineering Majorana zero modes. The platform consists of a ferromagnetic metallic wire placed among conventional superconductors, which are in proximity to ferromagnetic insulators. We demonstrate that Majorana zero modes emerge localised at the edges of the ferromagnetic wire, due to the interplay of the applied supercurrents and the induced by proximity exchange fields with conventional superconductivity. Our mechanism does not rely on the pairing of helical fermions by combining conventional superconductivity with spin-orbit coupling, but rather exploits the misalignment between the magnetization of the ferromagnetic insulators and that of the ferromagnetic wire.