Efficient energy transfer and photoluminescence enhancement in 2D MoS2/bulk InSe van der Waals heterostructures
Michael Altvater, Christopher E. Stevens, Nicholas A. Pike, Joshua R. Hendrickson, Rahul Rao, Sergiy Krylyuk, Albert V. Davydov, Deep Jariwala, Ruth Pachter, Michael Snure, Nicholas R. Glavin
Abstract
Abstract Heterostructures between 2D and 3D electron systems remain critically important in developing novel and efficient optoelectronic and electronic devices. In this study, a vertical heterojunction between monolayer MoS 2 and bulk InSe was developed. This heterojunction exhibits a type-I band alignment that facilitates rapid energy transfer from the wide bandgap MoS 2 to the narrow bandgap InSe resulting in quenching of the MoS 2 photoluminescence (PL) emission and enhancement of the A exciton emission in InSe. Temperature-dependent PL measurements of MoS 2 on SiO 2 , MoS 2 on InSe, and bare InSe revealed the critical role of defect trapping and electron-phonon coupling in the optical response of MoS 2 on InSe. These results demonstrate that heterostructures combining monolayer MoS 2 on bulk InSe, showing marked improvement relative to bare InSe, would be advantageous when incorporated into optoelectronic devices such as photodetectors, light emitters, and color converters and highlights the benefit of creating van der Waals (vdW) heterostructures with tailored properties.