Majorana fermions in spin-singlet nodal superconductors with coexisting non-collinear magnetic order

TL;DR

This paper proposes a new method to realize Majorana fermions in spin-singlet nodal superconductors by introducing non-collinear magnetic order, leading to topological phases with stable Majorana bound states.

Contribution

It introduces a novel approach to generate Majorana fermions in superconductors through non-collinear magnetic order, applicable to extended t-J models on various lattices.

Findings

Non-collinear magnetic order induces topological superconductivity.

Majorana bound states appear in vortex cores, magnetic defects, and edges.

Potential realization in correlated electron materials with nodal superconductivity and magnetism.

Abstract

Realizations of Majorana fermions in solid state materials have attracted great interests recently in connection to topological order and quantum information processing. We propose a novel way to create Majorana fermions in superconductors. We show that an incipient non-collinear magnetic order turns a spin-singlet superconductor with nodes into a topological superconductor with a stable Majorana bound state in the vortex core; at a topologically-stable magnetic point defect; and on the edge. We argue that such an exotic non-Abelian phase can be realized in extended t-J models on the triangular and square lattices. It is promising to search for Majorana fermions in correlated electron materials where nodal superconductivity and magnetism are two common caricatures.