Phys.org December 15, 2023 Researchers at the University of Kansas formed heterostructure by sandwiching a MoS2 and MoSe2 heterobilayer between two graphene monolayers. Transient absorption measurements revealed that the electrons and holes separated by the type-II interface between MoS2 and MoSe2 could transfer to the two graphene layers, respectively. With high spatial and temporal resolution, they found that while the holes in one graphene layer undergoes a classical diffusion process with a large diffusion coefficient of 65 cm2 s–1 and a charge mobility of 5000 cm2 V–1 s–1, the electrons in the other graphene layer exhibits a quasi-ballistic transport feature. […]