An All-Day Lidar For Detecting Soft Targets Over 100 Km Based On Superconducting Nanowire Single-Photon Detectors

It is a big challenge for lidar to detect soft targets over long distances in the atmosphere due to the low reflection of soft targets and the strong atmospheric attenuation. In this paper, we propose an all-day lidar system based on the 4 pixel array superconducting nanowire single-photon detectors. This significantly improves the detection efficiency of the aerosol and other targets by utilizing the advantages of high sensitivity, low dark count rate, wide dynamic range and photon number resolution. The system detects both soft targets and hard targets 100 km away in the atmosphere. In experiments, based on the photon-number resolving detection method, the lidar detects and distinguishes soft and hard targets simultaneously 50 km away during the day. Furthermore, the system obtains the wind field information in the atmosphere by monitoring clouds at a distance exceeding 86 km. The detection results indicate that the system is promising for applications as a long distance all-day lidar.