High-performance near-infrared photodetectors based on gate-controlled graphene–germanium Schottky junction with split active junction

Abstract The structure of a gate-controlled graphene/germanium hybrid photodetector was optimized by splitting the active region to achieve highly sensitive infrared detection capability. strengthened internal electric field in split junctions enabled efficient collection photocarriers, resulting responsivity 2.02 A W −1 and specific detectivity 5.28 × 10 Jones with reduced dark current improved external quantum efficiency; these results are more than doubled compared 0.85 1.69 for single junction device. is 1.7, 2.7, 39 times higher that previously reported graphene/Ge Al 2 O 3 interfacial layer, graphene/Ge, simple heterostructure photodetectors, respectively.