Two-dimensional topological superconductivity with antiferromagnetic insulators

TL;DR

This paper proposes a new method to realize two-dimensional topological superconductivity using interfaces between antiferromagnets and conventional superconductors, avoiding complex engineering and relying on intrinsic properties.

Contribution

It introduces a novel approach utilizing antiferromagnetic insulators to engineer topological superconductivity through solitonic interface states.

Findings

Interfacial solitonic states are topologically protected.

The proposed states do not require fine-tuning.

Intrinsic spin-orbit coupling gaps stabilize the phase.

Abstract

Two-dimensional topological superconductivity has attracted great interest due to the emergence of Majorana modes bound to vortices and propagating along edges. However, due to its rare appearance in natural compounds, experimental realizations rely on a delicate artificial engineering involving materials with helical states, magnetic fields and conventional superconductors. Here we introduce an alternative path using a class of three-dimensional antiferromagnet to engineer a two- dimensional topological superconductor. Our proposal exploits the appearance of solitonic states at the interface between a topologically trivial antiferromagnet and a conventional superconductor, which realize a topological superconducting phase when their spectrum is gapped by intrinsic spin- orbit coupling. We show that these interfacial states do not require fine-tuning, but are protected by asymptotic boundary conditions.