Tuning optical properties of Graphene/WSe2 heterostructure by introducing vacancy: First principles calculations

Abstract

Abstract The effects of W and Se vacancies on the electronic structure and optical properties in Graphene/WSe2 heterostructure (GW) are studied based on the density functional theory. It is found that both the formation of the heterostructures and the introduction of the W or Se vacancies have great impactions on the electronic structure of WSe2. Additionally, after W or Se vacancies are introduced in GW, the optical properties are greatly red-shifted and the values of the optical parameters become larger than those of the pure GW. In particular, the effects of the W vacancy is greater than that of the Se vacancy. These theoretical results indicate that the introduction of vacancies does tune the electronic structure and the optical properties of the GW heterostructures, which provide a useful guidance for the design of novel optical nanodevices based on two dimensional heterostructures.