Correlated states in transition metal dichalcogenide heterobilayer moiré superlattices*

2D van der Waals moiré superlattices have attracted much attention recently as highly tunable platforms to study strong correlation phenomena. In particular, transition metal dichalcogenide (TMD) heterobilayers at small twist angles develop isolated flat moiré bands that are accurately described [1] by triangular lattice (generalized) Hubbard models. Using a fully self-consistent mean-field-theory, we investigate the competing correlated phases at various fractional filling factors and twist angle, and identify metal-Mott insulator phase transition at 1/2 band filling and Wigner crystal phases at 1/6 band filling. We will discuss the relationship between our calculations and recent related experiments.

[1] Wu, F., Lovorn, T., Tutuc, E., & MacDonald, A. H. (2018). Hubbard model physics in transition metal dichalcogenide moiré bands. Physical review letters, 121(2), 026402.