Abstract
Since the very recent discovery of unconventional superconductivity in twisted WSe(2) homobilayers at filling ν = - 1, considerable interest has arisen in revealing its mechanism. In this paper, we developed a three-band tight-binding model with non-trivial band topology by direct Wannierization of the low-energy continuum model. Incorporating both onsite Hubbard repulsion and next-nearest-neighbor attraction, we then performed a mean-field analysis of the microscopic model and obtained a phase diagram qualitatively consistent with the experiment results. For zero or weak displacement field, the ground state is a Chern number C = ± 2 topological superconductor in the Altland-Zirnbauer A-class (breaking time-reversal but preserving total S(z) symmetry) with inter-valley pairing dominant in dxy ± idx2-y2 -wave (mixing with a subdominant p(x) ∓ ip(y)-wave) component. For a relatively strong displacement field, the ground state is a correlated insulator with the 120° antiferromagnetic order. Our results provide new insights into the nature of the twisted WSe(2) systems and suggest the need for further theoretical and experimental explorations.