Evaluation of the Single-Photon Detector Characteristics Depending on the Parameters of a WxSi1 – x Superconducting Film

• Published in: Physics of the solid state Vol. 63; no. 9; pp. 1410 - 1413
• Main Authors: Hydyrova, S. Yu, Stepanov, I. A., Vasilev, D. D., Moiseev, K. M.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.09.2021; Springer Nature B.V
• Subjects: Critical temperature; Cut off wavelength; Mathematical analysis; Photons; Physics; Physics and Astronomy; Recovery time; Sensors; Solid State Physics; Superconductivity; critical temperature; sheet resistance; superconductivity; superconducting nanowire single-photon detector (SNSPD); sensitive element; detector efficiency; Si; W; thin film; detector count rate
• ISSN: 1063-7834; 1090-6460
• DOI: 10.1134/S106378342109016X

The absorption efficiency, cutoff wavelength, and recovery time of a superconducting single-photon detector depending on sheet resistance R s and critical temperature T с of the W x Si 1 –   x film were calculated. The calculated dependences of the detector characteristics for the W x Si 1 –   x films show that the films with T c  > 3.5 K and 300 < R s < 420 Ω/sq will provide η abs ≈ 15–20% and η IDE = 100% at a radiation wavelength of 1550 nm and a detector recovery time of τ < 40 ns, which corresponds to the possible detector count rate CR max = 25 MHz.