Evidence for Moiré Trions in Twisted MoSe2 Homobilayers

Nano Lett. 2021 May 26;21(10):4461-4468. doi: 10.1021/acs.nanolett.1c01207. Epub 2021 May 10.

Abstract

Moiré superlattices of van der Waals structures offer a powerful platform for engineering band structure and quantum states. For instance, Moiré superlattices in magic-angle twisted bilayer graphene, ABC trilayer graphene have been shown to harbor correlated insulating and superconducting states, while in transition metal dichalcogenide (TMD) twisted bilayers, Moiré excitons have been identified. Here we show that the effects of a Moiré superlattice on the band structure are general: In TMD twisted bilayers, excitons and exciton complexes can be trapped in the superlattice in a manner analogous to ultracold bosonic or Fermionic atoms in optical lattices. Using twisted MoSe2 homobilayers as a model system, we present evidence for Moiré trions. Our results thus open possibilities for designer van der Waals structures hosting arrays of Fermionic or bosonic quasiparticles, which can be used to realize tunable many-body states crucial for quantum simulation and quantum information processing.

Keywords: Moiré excitons; Moiré trions; transition metal dichalcogenides; twisted homobilayers; two-dimensional materials; van der Waals heterostructures.