Synergistic Effects of Plasmonics and Electrons Trapping in Graphene Short-Wave Infrared Photodetectors with Ultrahigh Responsivity (original) (raw)

Graphene's unique electronic and optical properties have made it an attractive material for developing ultrafast short-wave infrared (SWIR) photodetectors. However, the performance of graphene SWIR photodetectors has been limited by the low optical absorption of graphene, as well as the ultrashort lifetime of photoinduced carriers. Here, we present two mechanisms to overcome these two shortages and demonstrate graphene-based SWIR photodetector with high responsivity and fast photoresponse. Particularly, a vertical built-in field is employed onto the graphene channel for trapping the photo-induced electrons and leaving holes in graphene, which results in the prolonging of photoinduced carrier lifetime. On the other hand, plasmonic effect employed to realize photon trapping and enhance the light absorption of graphene. Thanks to the above two mechanisms, the responsivity of this proposed SWIR photodetector is up to a record of 83 A/W at the wavelength of 1.55 μm with a fast rising...