Topological superconductivity in a spin-orbit coupled Kondo lattice

TL;DR

This paper explores how spin-orbit coupling induces topological superconductivity in a 2D Kondo lattice model, leading to Majorana edge modes and a chiral topological superconductor with potential relevance to heavy fermion materials.

Contribution

It introduces a model showing how Rashba spin-orbit interaction and Kondo coupling produce a topological superconductor with Majorana modes in a Kondo lattice system.

Findings

Majorana bands become gapped with non-zero Chern numbers

Unidirectional Majorana edge modes emerge

Model suggests relevance to heavy fermion superconductors like UTe$_2$

Abstract

We consider the effect of spin-orbit coupling on a two-dimensional Kondo Lattice model, in which conduction electrons are antiferromagnetically coupled to a Yao-Lee spin liquid. When a Rashba spin-orbit interaction and a nearest-neighbor Kondo interaction is introduced, the low-energy Majorana bands become gapped and develop Chern numbers, protecting unidirectionally propagating Majorana edge modes. Our model describes a chiral topological superconductor with fractionalized charge-$e$ order parameter and spontaneously broken time-reversal symmetry, which may be of interest for certain heavy fermion superconductors, such as UTe$_2$.