Strong correlation and topology in 2D semiconductor moiré superlattices

Moiré superlattices formed in van der Waals materials have emerged as a new platform to explore strong correlation physics and topological physics in two-dimensional (2D) electronic systems. In this talk, I will mainly present electronic transport and compressibility studies of moiré superlattices built on 2D transition metal dichalcogenide (TMDc) semiconductors. A series of correlation-driven states, including Mott insulators [1], generalized Wigner crystals [2], and stripe phases [3], formed at either integer or fractional filling factors of the moiré superlattice. Benefiting from the extraordinary tunability of the system, an interaction-driven Mott transition has been realized experimentally [4]. Furthermore, we found the band topology also plays an important role in TMDc moiré superlattice, which enable us to realize a quantum anomalous Hall state in TMDc moiré superlattice [5]. Our studies pave the path for discovery of a wealth of emergent phenomena arising from the combined influence of strong correlation and topology in TMDc moiré superlattice.