High performance superconductor single photon detector with enhanced system efficiency at infrared wavelength

Single photon detection technology is a frontier in the field of photon detection. As a newly developed technique, superconductor single photon detector (SSPD) has many attractive advantages such as wide response bandwidth, low noise, and fast speed. In this paper, we experimentally demonstrate a high performance SSPD with large system efficiency and low dark count rate at infrared wavelengths. The devices structure, fabrication process and system performance are presented in details. For our SSPD, we achieve a system efficiency of 60% at 1550 nm with a dark count rate of 100 cps. The time jitter and the maximum repetition rate are also measured to be 46 ps and 50 MHz respectively.