Possible topological superconducting phases of MoS2

Phys Rev Lett. 2014 Aug 29;113(9):097001. doi: 10.1103/PhysRevLett.113.097001. Epub 2014 Aug 26.

Abstract

Molybdenum disulphide (MoS2) has attracted much interest in recent years due to its potential applications in a new generation of electronic devices. Recently, it was shown that thin films of MoS2 can become superconducting with a highest Tc of 10 K when the material is heavily gated to the conducting regime. In this work, using the group theoretical approach, we determine the possible pairing symmetries of heavily gated MoS2. Depending on the electron-electron interactions and Rashba spin-orbit coupling, the material can support an exotic spin-singlet p+ip-wavelike, an exotic spin-triplet s-wavelike, and a conventional spin-triplet p-wave pairing phase. Importantly, the exotic spin-singlet p+ip-wave phase is a topological superconducting phase that breaks time-reversal symmetry spontaneously and possesses nonzero Chern numbers where the Chern number determines the number of branches of chiral Majorana edge states.