Possible Topological Superconducting Phases of MoS$_{2}$

TL;DR

This paper explores the potential topological superconducting phases in heavily gated MoS$_2$, identifying possible exotic pairing symmetries, including a topological phase with Majorana edge states, using group theoretical analysis.

Contribution

It determines the possible pairing symmetries of superconducting MoS$_2$ under gating, revealing exotic topological phases not previously characterized.

Findings

MoS$_2$ can support exotic spin-singlet $p+ip$-wave-like pairing.

Topological superconducting phase with chiral Majorana edge states identified.

Multiple pairing symmetries depend on electron-electron interactions.

Abstract

Molybdenum disulphide (MoS$_2$) 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 MoS$_2$ can become superconducting with a highest $T_{c}$ of 10K 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 MoS$_2$. Depending on the electron-electron interactions, the material can support an exotic spin-singlet $p +ip $-wave-like, an exotic spin-triplet s-wave-like and an conventional spin-triplet $p$-wave pairing phases. Importantly, the exotic spin-singlet $p+ip$-wave phase is a topological superconducting phase which breaks time-reversal symmetry spontaneously and possesses chiral Majorana edge states.