Fig. 1: Transfer process of the photo-generated carriers.
a Optical image of graphene transferred onto a GaAs substrate and the cross-sectional TEM image of the interface of the graphene/GaAs vdW heterostructure. The scale bars used in the optical image and the cross-sectional TEM image are 10 μm and 5 nm, respectively. b The exchange of C and Ga or As atoms at the graphene/GaAs vdW heterostructure induced by FLI. c–f The illustration of different transfer processes for the photo-generated carriers for c InAs/GaAs QDs, d the non-irradiated graphene/GaAs vdW heterostructure, e the graphene/GaAs vdW heterostructure irradiated increasing power densities of femtosecond laser pulses, and f the graphene/GaAs vdW heterostructure capped with the different layers of graphene, where the funnel depicts the enlarged photon harvest and carrier generation by graphene, L1–L5 describe increasing carrier transfer efficiencies caused by the FLI, and A1–A5 represent the optical absorption of the graphene with increased layer numbers.
