Magnetic field driven nodal topological superconductivity in monolayer transition metal dichalcogenides

By Wen-Yu He, Benjamin T. Zhou, J. J. He, N. Yuan, Ting Zhang, K. T. Law. Communications Physics, 2016

133 citations recorded by the source corpus.

Recently, Ising superconductors that possess in-plane upper critical fields Hc2 much larger than the Pauli limit field are under intense experimental study. Many monolayer or few layer transition metal dichalcogenides are shown to be Ising superconductors. Here we show that in a wide range of experimentally accessible regimes where the in-plane magnetic field is higher than the Pauli limit field but lower than Hc2, a 2H-structure monolayer NbSe2 or similarly TaS2 becomes a nodal topological superconductor. The bulk nodal points appear on the Γ−M lines of the Brillouin zone where the Ising SOC vanishes. The nodal points are connected by Majorana flat bands, and the flat bands are associated with a large number of Majorana zero energy edge modes that induce spin-triplet Cooper pairs. This work demonstrates an experimentally feasible way to realize Majorana fermions in nodal topological superconductor, without any fine-tuning of experimental parameters.There are many different types of superconducting phases each with unique properties and mechanisms behind their superconductivity. The authors investigate a type of superconductor called an Ising superconductor and demonstrate that by application of a magnetic field they can be driven into a nodal superconducting phase.

Subfields: Atomic and Molecular Physics, and Optics, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/a77931e9ebced20d41f143d7aa3703676ffa2a7d