▎ 摘　　要

A double-cavity graphene photodetector consisting of filtering cavity and absorption cavity with high performance is proposed. The device has an ultranarrow response linewidth and high quantum efficiency as well as high response speed. By taking full advantage of the double cavity, the structure parameters of the photodetector are deeply optimized, and 88% peak quantum efficiency with 0.75-nm linewidth is obtained. It is believed that the double-cavity graphene photodetector has promising and potential application in a high-speed density wavelength-division multiplexing system. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)