Waveguide-Intergrated Superconducting Nanowire Avalanche Single-Photon Detectors

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

Abstract

Superconducting nanowire single-photon detectors (SNSPDs) are of great interest for applications in quantum communication, quantum information and quantum computing. A drawback of SNSPDs, however, is the low signal-to-noise ratio of their electrical output signals, resulting from operating at bias currents below the critical current of the ultra-thin superconducting nanowires. High signal-to-noise ratio can be achieved by implementing a superconducting nanowire avalanche single photon detector (SNAP) architecture that connects several SNSPD elements in parallel, thus realising operation at high bias current and successive switching of elements upon photon absorption and current redistribution. Here we show the design, fabrication and measurements of a successive-avalanche architecture SNAP with amorphous molybdenum silicide nanowires integrated with nanophotonic waveguides for on-chip single-photon counting with ultra-high signal-to-noise ratios.