Superconducting single-photon detector made of MoSi film

Abstract

We fabricated and characterised nanowire superconducting single-photon detectors (SSPDs) made of 4 nm thick amorphous Mo$_x$Si$_{1-x}$ films. At 1.7 K the best devices exhibit a detection efficiency up to 18% at 1.2 um wavelength of unpolarised light, a characteristic response time of about 6 ns and timing jitter of 120 ps. The detection efficiency was studied in wavelength range from 650 nm to 2500 nm. At wavelengths below 1200 nm these detectors reach their maximum detection efficiency limited by photon absorption in the thin MoSi film.