A three-dimensional, polarization-insensitive superconducting nanowire avalanche photodetector
Varun Boehm Verma, Francesco Marsili, Sean David Harrington, Adriana E. Lita, Richard P. Mirin, Sae Woo Nam · Applied Physics Letters · 2012
We demonstrate an approach to improving the detection efficiency, removing the polarization dependence, and increasing the signal-to-noise ratio of conventional superconducting nanowire single photon detectors (SNSPDs) by vertically stacking two WSi SNSPDs and electrically connecting them in parallel, forming a three-dimensional superconducting nanowire avalanche photodetector. We measure a peak system detection efficiency of 87.7% ± 0.5% and a polarization dependence of less than 2%, representing nearly an order of magnitude improvement in both system detection efficiency and reduction of polarization dependence compared to conventional SNSPDs.