Gated mode superconducting nanowire single photon detectors.

Single Photon Detectors are fundamental to quantum optics and quantum information. Superconducting nanowire detectors exhibit high performance in free-running mode, but have a limited maximum count rate. By exploiting a bistable superconducting nanowire system, we demonstrate the first gated-mode operation of these detectors for a large active area single element device at 625MHz, one order of magnitude faster than its free-running counterpart. We show the maximum count rate in gated-mode operation can be pushed to GHz range without a compromise on the active area or quantum efficiency, while reducing the dark count rate.