Ultrafast reset time of superconducting single photon detectors

Abstract

We have measured the ultrafast reset time of NbN superconducting single photon detectors (SSPDs) based on a design consisting of N parallel superconducting stripes. Compared to a standard SSPD of identical active area, the parallel SSPD displays a similar detection efficiency and a kinetic inductance, which is divided by N2. For N=12, the duration of the voltage detection pulse is reduced by nearly two orders of magnitude down to 200 ps. The timing jitter associated with the rising front is only 16 ps. These results open a way to efficient detectors with ultrahigh counting rate exceeding 1 GHz. © 2008 American Institute of Physics.