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arXiv · 1201.1908

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

Yuan-Ming Lu·Ziqiang Wang
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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.

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Yuan-Ming Lu, Ziqiang Wang. 2012-01-09. Majorana fermions in spin-singlet nodal superconductors with coexisting non-collinear magnetic order. https://doi.org/10.1103/physrevlett.110.096403

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