Approximate symmetries, insulators, and superconductivity in continuum-model description of twisted WSe${}_2$

Abstract

Motivated by the recent discovery of superconductivity in twisted bilayer WSe${}_2$, we analyze the correlated physics in this system in the framework of a continuum model for the moiré superlattice. Using the symmetries in a fine-tuned limit of the system, we identify the strong-coupling ground states and their fate when the perturbations caused by finite bandwidth, displacement field, and the phase of the intralayer potential are taken into account. We classify the superconducting instabilities and, employing a spin-fermion-like model, study the superconducting instabilities in proximity to these insulating particle-hole orders. This reveals that only a neighboring intervalley coherent phase (with zero or finite wave vector) is naturally consistent with the observed superconducting state. Depending on details, the superconductor will be nodal or a chiral gapped state while further including electron-phonon coupling leads to a fully gapped, time-reversal symmetric pairing state.

11 pages, 9 figures

References in corpus (8)

• Continuum Model of the Twisted Bilayer
• The insulator/Chern-insulator transition in the Haldane model
• Superconductivity in twisted bilayer WSe${}_2$
• TSTG II: Projected Hartree-Fock Study of Twisted Symmetric Trilayer Graphene
• Superconductivity in twisted transition metal dichalcogenide homobilayers
• Theory of Correlated Insulators and Superconductor at $\nu =1$ in Twisted WSe${}_2$
• Topological superconductivity with mixed singlet-triplet pairing in moiré transition-metal-dichalcogenide bilayers
• Band theory for heterostructures with interface superlattices

Cited by in corpus (5)

• Theory of intervalley-coherent AFM order and topological superconductivity in tWSe${}_2$
• Topological Chiral Superconductivity Mediated by Intervalley Antiferromagnetic Fluctuations in Twisted Bilayer WSe${}_2$
• Angle evolution of the superconducting phase diagram in twisted bilayer WSe2
• Quantum Phases in Twisted Homobilayer Transition Metal Dichalcogenides
• Site-polarized Mott phases competing with a correlated metal in twisted WSe${}_2$