Broadband surface plasmon resonance enhanced self-powered graphene/GaAs photodetector with ultrahigh detectivity

By the surface plasmon resonance enhanced light-matter interaction of Ag nanoparticles, the responsivity and detectivity of graphene/GaAs heterojunction photodetector for the broadband range (325−980 nm) are greatly enhanced. For the incident light of 405 nm, the detectivity can be increased by 202% and reach a large value of 2.98 × 1013 Jones. The physical mechanism originates from the overlap the depletion region of graphene/GaAs heterostructure, the surface plasmon enhanced light field region below the surface and the optical absorption region of the GaAs layer. This high performance broadband self-powered photodetector is a promising candidate for sensitive charge coupled displayer.285