Excitonphotophysics in MoSe₂-WSe₂ Moiré hetero-bilayers

The stacking of 2D materials in Moiré heterobilayers provide a novel platform to study intra and interlayer excitons. Of interest for quantum science is the bilayers exhibit a natural and periodic trapping potential that enables a spatially periodic array of programmable quantum em itters. In this talk we discuss the MoSe₂-WSe₂ system. The atomically sharp interface between the two monolayers creates an effective type-2 heterojunction that allows ultrafast charge transfer and the existence of trapped interlayer excitons upon optical excitation. Our work investigates and elucidates the nature of the quantum emitter ensemble in these materials. We demonstrate the existence of valley coherence for trapped trions, excitons, and biexcitons. Our results contribute to an understanding of trapped excitonic species in these systems and how they may be utilized for quantum information storage.