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arXiv · 1903.04830

Time-reversal symmetry breaking superconductivity in hole-doped monolayer MoS$_{2}$

Rikuto Oiwa·Yuki Yanagi·Hiroaki Kusunose
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Abstract

We investigate the nature of the time-reversal breaking pairing state in the hole-doped monolayer MoS$_{2}$ on the basis of the realistic three-orbital attractive Hubbard-like model with the atomic spin-orbit coupling. Due to the multi-band features arising from the Mo $d$ orbitals in the noncentrosymmetric crystal structure, the Lifshitz transition takes place upon hole doping. Across the Lifshitz transition point, the sign of the relative phase between the Cooper-pair components drastically changes, leading to the emergence of the time-reversal breaking phase with complex gap functions. It is shown that this intriguing pairing state is characterized by the finite momentum-space distributions of the orbital and spin angular momentum with three-fold rotational symmetry on the Fermi-surface pockets around K and K$'$ points. The present mechanism for the time-reversal breaking superconductivity can ubiquitously be applied to spin-orbit-coupled metals in noncentrosymmetric crystal structures.

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Rikuto Oiwa, Yuki Yanagi, Hiroaki Kusunose. 2019-03-12. Time-reversal symmetry breaking superconductivity in hole-doped monolayer MoS$_{2}$. https://doi.org/10.7566/jpsj.88.063703

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