Spin-polarized edge modes between different magnet-superconductor-hybrids

TL;DR

This study investigates spin-polarized edge modes at the boundary between two different topological magnet-superconductor hybrids, revealing spin-polarized chiral edge states with potential for topology-based applications.

Contribution

It demonstrates the existence of spin-polarized edge modes between different topological superconductors using experimental and theoretical methods.

Findings

Observation of spin-polarized low-energy modes at the boundary.

Explanation of edge modes via a tight-binding model.

Identification of spin-polarized chiral edge modes connecting topological nodal points.

Abstract

The interplay of magnetism and superconductivity can lead to intriguing emergent phenomena. Here we combine two different two-dimensional antiferromagnetic magnet-superconductor hybrids (MSH) and study their properties using spin-polarized scanning tunneling microscopy. Both MSHs show the characteristics of a topological nodal point superconducting phase with edge modes to the trivial substrate superconductor. At the boundary between the two MSHs we find low-energy modes which are spin-polarized. Based on a tight-binding model we can explain the experimental observations by considering two different topological nodal point superconductors. This gives rise to spin-polarized chiral edge modes that connect topological nodal points of the two different MSH. We demonstrate via the complex band structure that due to an asymmetric lateral decay these edge modes are spin-polarized, regardless of the details of the spin structure at the boundary. The presence of spin-polarized edge states between different topological superconductors enables advanced functional design for the exploitation of MSHs as a platform for topology-based applications.