Paper detail

Design of micron-long superconducting nanowire perfect absorber for efficient high speed single-photon detection

Despite very efficient superconducting nanowire single-photon detectors (SNSPDs) reported recently, combining their other performance advantages such as high speed and ultra-low timing jitter in a single device still remains challenging. In this work, we present a perfect absorber model and corresponding detector design based on a micron-long NbN nanowire integrated with a 2D-photonic crystal cavity of ultra-small mode volume, which promises simultaneous achievement of near-unity absorption, gigahertz counting rates and broadband optical response with a 3 dB bandwidth of 71 nm. Compared to previous stand-alone meandered and waveguide-integrated SNSPDs, this perfect absorber design addresses the trade space in size, efficiency, speed and bandwidth for realizing large on-chip single-photon detector arrays.