▎ 摘　　要

In this paper, a graphene/GaAs near-infrared photodetector with Ag nanoparticles (NPs) is fabricated and the photoelectric characteristics of the device under near-infrared light is investigated. By spin-coating a 30 nm Ag NPs layer on the surface of the device, the local surface plasmon resonance (LSPR) of the Ag NPs can enhance the absorption of near-infrared light, thereby improving the sensitivity of the device. Compared with the device without Ag NPs, the responsivity of the device is significantly increased to 96 mA/W (increased by 1.6 times) under zero bias voltage at 808 nm near infrared light, the maximum detectivity of the device can be up to 4.72 x 1011 cm Hz1/2W- 1. In addition, the response time (tau r) and recovery time (tau f) of the device are 28.21 mu s/68.11 mu s. The quantum efficiency of the detector is increased from 37% to 84% compared with the device without Ag NPs. This result shows the graphene/GaAs photodetectors have a broad application prospect in the field of nearinfrared detection.