Waveguide-Intergrated Superconducting Nanowire Avalanche Single-Photon Detectors

Graham-Scott, Connor A.; Baldauf, Erik M.; Häußler, Matthias; Mikhailov, Mikhail Yu.; Schuck, Carsten

Abstract

Superconducting nanowire single-photon detectors (SNSPDs) are of great interest for applications in quantum sciences and technologies. SNSPDs fabricated from amorphous superconducting thin films adapt to a wide range of substrate-materials and show high sensitivities over broad spectral range. A drawback of these however is a low signal-to-noise ratio of the electrical output resulting from a lower critical current when operated close to the superconductor*s critical temperature in user-friendly cost-efficient cryogenic systems. This challenge can be overcome by parallelizing SNSPDs in an avalanche system to create a superconducting nanowire avalanche single photon detector (SNAP). Here we show how SNAPs can be integrated with nanophotonic circuitry to allow for on-chip single-photon counting with ultra-high signal-to-noise ratio. We furthermore present simulation results on how the SNAP architecture can benefit both internal and absorption efficiencies of waveguide-integrated SNSPDs.