IEICE Transactions on Electronics
Spectral Sensitivity of the NbN Single-Photon Superconducting Detector
Roman Sobolewski, Ying Xu, Xuemei Zheng, Carlo Kosik Williams, J. Zhang, A. Verevkin, Чулкова Галина Меркурьевна, Alexander A. Korneev, Andrey P. Lipatov, Oleg V. Okunev, Смирнов Константин Владимирович, Non-members
Abstract
SUMMARY We report our studies on the spectral sensitivity of superconducting NbN thin-film single-photon detectors (SPD’s)capable of GHz counting rates of visible and nearinfrared photons. In particular, it has been shown that a NbN SPD is sensitive to 1.55-µm wavelength radiation and can be used for quantum communication. Our SPD’s exhibit experimentally measured intrinsic quantum efficiencies from 20% at 800 nm up to ∼1% at 1.55-µm wavelength. The devices demonstrate picosecond response time (< 100 ps, limited by our readout system)and negligibly low dark counts. Spectral dependencies of photon counting of continuous-wave, 0.4-µm to 3.5-µm radiation, and 0.63-µm, 1.33-µm, and 1.55-µm laser-pulsed radiations are presented for the single-stripe-type and meander-type devices.