|
Korneev, A., Minaeva, O., Rubtsova, I., Milostnaya, I., Chulkova, G., Voronov, B., et al. (2005). Superconducting single-photon ultrathin NbN film detector. Quantum Electronics, 35(8), 698–700.
Abstract: Superconducting single-photon ultrathin NbN film detectors are studied. The development of manufacturing technology of detectors and the reduction of their operating temperature down to 2 K resulted in a considerable increase in their quantum efficiency, which reached in the visible region (at 0.56 μm) 30%—40%, i.e., achieved the limit determined by the absorption coefficient of the film. The quantum efficiency exponentially decreases with increasing wavelength, being equal to ~20% at 1.55 μm and ~0.02% at 5 μm. For the dark count rate of ~10-4s-1, the experimental equivalent noise power was 1.5×10-20 W Hz-1/2; it can be decreased in the future down to the record low value of 5×10-21 W Hz-1/2. The time resolution of the detector is 30 ps.
|
|
|
Verevkin, A., Zhang, J., Sobolewski, R., Lipatov, A., Okunev, O., Chulkova, G., et al. (2002). Detection efficiency of large-active-area NbN single-photon superconducting detectors in the ultraviolet to near-infrared range. Appl. Phys. Lett., 80(25), 4687–4689.
Abstract: We report our studies on spectral sensitivity of meander-type, superconducting NbN thin-film single-photon detectors (SPDs), characterized by GHz counting rates of visible and near-infrared photons and negligible dark counts. Our SPDs exhibit experimentally determined quantum efficiencies ranging from ∼0.2% at the 1.55 μm wavelength to ∼70% at 0.4 μm. Spectral dependences of the detection efficiency (DE) at the 0.4 to 3.0-μm-wavelength range are presented. The exponential character of the DE dependence on wavelength, as well as its dependence versus bias current, is qualitatively explained in terms of superconducting fluctuations in our ultrathin, submicron-width superconducting stripes. The DE values of large-active-area NbN SPDs in the visible range are high enough for modern quantum communications.
|
|
|
Verevkin, A., Slysz, W., Pearlman, A., Zhang, J., Sobolewski, R., Okunev, O., et al. (2003). Real-time GHz-rate counting of infrared photons using nanostructured NbN superconducting detectors. In CLEO/QELS (CThM8). Optical Society of America.
Abstract: We demonstrate that our ultrathin, nanometer-width NbN superconducting single-photon detectors are capable of above 1-GHz-frequency, real-time counting of near-infrared photons. The measured system jitter of the detector is below 15 ps.
|
|
|
Verevkin, A., Zhang, J., Slysz, W., Sobolewski, R., Lipatov, A., Okunev, O., et al. (2002). Spectral sensitivity and temporal resolution of NbN superconducting single-photon detectors. In Proc. 13th Int. Symp. Space Terahertz Technol. (pp. 105–111).
Abstract: We report our studies on spectral sensitivity and time resolution of superconducting NbN thin film single-photon detectors (SPDs). Our SPDs exhibit an everimentally measured detection efficiencies (DE) from — 0.2% at 2=1550 nm up to —3% at lambda=405 nm wavelength for 10-nm film thickness devices and up to 3.5% at lambda=1550 nm for 3.5-nm film thickness devices. Spectral dependences of detection efficiency (DE) at 2=0.4 —3.0 pm range are presented. With variable optical delay setup, it is shown that NbN SPD potentially can resolve optical pulses with the repetition rate up to 10 GHz at least. The observed full width at the half maximum (FWHM) of the signal pulse is about 150-180 ps, limited by read-out electronics. The jitter of NbN SPD is measured to be —35 ps at optimum biasing.
|
|
|
Ptitsina, N. G., Chulkova, G. M., & Gershenzon, E. M. (1995). Influence of the interference of electron-phonon and electron-impurity scattering on the conductivity of unordered Nb films. JETP, 80(5), 960–964.
Abstract: The temperature dependence of the resistivity of Nb thin films has been studied at T=4.2-300 K. It has been shown that quantum interference between electron-phonon and electron-impurity scattering determines the temperature dependence of the resistivity of the films investigated over a broad temperature range. The magnitude of the contribution of the electron-phonon-impurity,interference is described satisfactorily by the theory developed by Reizer and Sergeev {Zh. Eksp. Teor. Fiz. 92,2291 (1987) [Sov. Phys. JETP 65, 1291 (1987)l). The interaction constants of electrons with longitudinal and transverse phonons in Nb films have been determined for the first time by comparing the experimental data with the theory. The values of the constants obtained are consistent with the data on the inelastic electron-phonon scattering times in the films investigated. The contribution of the transverse phonons is dominant both in the interference correction to the resistivity and in the electron energy relaxation.
|
|
|
Korneev, A., Korneeva, Y., Manova, N., Larionov, P., Divochiy, A., Semenov, A., et al. (2013). Recent nanowire superconducting single-photon detector optimization for practical applications. IEEE Trans. Appl. Supercond., 23(3), 2201204 (1 to 4).
Abstract: In this paper, we present our approaches to the development of fiber-coupled superconducting single photon detectors with enhanced photon absorption. For such devices we have measured detection efficiency in wavelength range from 500 to 2000 nm. The best fiber coupled devices exhibit detection efficiency of 44.5% at 1310 nm wavelength and 35.5% at 1550 nm at 10 dark counts per second.
|
|
|
Gol’tsman, G., Korneev, A., Tarkhov, M., Seleznev, V., Divochiy, A., Minaeva, O., et al. (2007). Middle-infrared ultrafast superconducting single photon detector. In 32nd IRMW / 15th ICTE (pp. 115–116).
Abstract: We present the results of the research on quantum efficiency of the ultrathin-film superconducting single-photon detectors (SSPD) in the wavelength rage from 1 mum to 5.7 mum. Reduction of operation temperature to 1.6 K allowed us to measure quantum efficiency of ~1 % at 5.7 mum wavelength with the SSPD made from 4-nm-thick NbN film. In a pursuit of further performance improvement we endeavored SSPD fabricating from 4-nm-thick MoRe film as an alternative material. The MoRe film exhibited transition temperature of 7.7K, critical current density at 4.2 K temperature was 1.1times10 6 A/cm 2 , and diffusivity 1.73 cmVs. The single-photon response was observed with MoRe SSPD at 1.3 mum wavelength with quantum efficiency estimated to be 0.04%.
|
|
|
Chulkova, G., Milostnaya, I., Tarkhov, M., Korneev, A., Minaeva, O., Voronov, B., et al. (2006). Superconducting single-photon nanostructured detectors for advanced optical applications. In Proc. Symposium on Photonics Technologies for 7th Framework Program (Vol. 400).
Abstract: We present superconducting single-photon detectors (SSPDs) based on NbN thin-film nanostructures and operated at liquid helium temperatures. The SSPDs are made of ultrathin NbN films (2.5-4 nm thick, Tc= 9-11K) as meander-shaped nanowires covering the area of 10× 10 µm2. Our detectors are operated at the temperature well below the critical temperature Tc and are DC biased by a current Ib close to the meander critical current Ic. The operation principle of the detector is based on the use of the resistive region in a narrow ultra-thin superconducting stripe upon the absorption of an incident photon. The developed devices demonstrate high sensitivity and response speed in a broadband range from UV to mid-IR (up to 6 µm), making them very attractive for advanced optical technologies, which require efficient detectors of single quanta and low-density optical radiation.
|
|
|
Korneev, A., Divochiy, A., Marsili, F., Bitauld, D., Fiore, A., Seleznev, V., et al. (2008). Superconducting photon number resolving counter for near infrared applications. In P. Tománek, D. Senderáková, & M. Hrabovský (Eds.), Proc. SPIE (Vol. 7138, 713828 (1 to 5)). Spie.
Abstract: We present a novel concept of photon number resolving detector based on 120-nm-wide superconducting stripes made of 4-nm-thick NbN film and connected in parallel (PNR-SSPD). The detector consisting of 5 strips demonstrate a capability to resolve up to 4 photons absorbed simultaneously with the single-photon quantum efficiency of 2.5% and negligibly low dark count rate.
|
|
|
Korneev, A. A., Divochiy, A. V., Vakhtomin, Y. B., Korneeva, Y. P., Larionov, P. A., Manova, N. N., et al. (2013). IR single-photon receiver based on ultrathin NbN superconducting film. Rus. J. Radio Electron., (5).
Abstract: We present our recent results in research and development of superconducting single-photon detector (SSPD). We achieved the following performance improvement: first, we developed and characterized SSPD integrated in optical cavity and enabling its illumination from the face side, not through the substrate, second, we improved the quantum efficiency of the SSPD at around 3 μm wavelength by reduction of the strip width to 40 nm, and, finally, we improved the detection efficiency of the SSPD-based single-photon receiver system up to 20% at 1550 nm and extended its wavelength range beyond 1800 nm by the usage of the fluoride ZBLAN fibres.
|
|