2022, Enhanced interlayer neutral excitons and trions in MoSe2/MoS2/MoSe2 trilayer heterostructure, Nano Research

2022, Enhanced interlayer neutral excitons and trions in MoSe2/MoS2/MoSe2 trilayer heterostructure, Nano Research

Abstract:

Van der Waals heterostructures have recently emerged, in which two distinct transitional metal dichalcogenide (TMD) monolayers are stacked vertically to form interlayer excitons (IXs), offing new opportunities for the design of optoelectronic devices. However, the bilayer heterostructure with type-II band alignment produces a low IX quantum yield. Here, we present the observation of interlayer neutral excitons and trions in the MoSe2/MoS2/MoSe2 trilayer heterostructure (Tri-HS). In comparison to 8 K bilayer heterostructure, the addition of a MoSe2 layer to the Tri-HS can significantly increase the quantum yield of IXs. We attribute two symmetrical type-II band alignments formed in the Tri-HS, which effectively promote the IX radiation recombination. By analyzing the photoluminescence (PL) spectrum of the IXs at cryogenic temperature, and the power dependence, the existence of the interlayer trions was confirmed. Our results provide a promising platform for the development of more efficient optoelectronic devices and the investigation of new physical properties of TMDs.

Keywords: transitional metal dichalcogenide, trilayer heterostructure, enhanced interlayer exciton effect, photoluminescence, interlayer exciton

Link:https://trebuchet.public.springernature.app/get_content/7cfdf99d-7c28-4f28-b072-fc504fc896d4

Wu2022_Article_EnhancedInterlayerNeutralExcit.pdf