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Author Lusche, R.; Semenov, A.; Korneeva, Y.; Trifonov, A.; Korneev, A.; Gol'tsman, G.; Hübers, H.-W.
Title Effect of magnetic field on the photon detection in thin superconducting meander structures Type Journal Article
Year 2014 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 89 Issue (up) 10 Pages 104513 (1 to 7)
Keywords NbN SSPD, SNSPD
Abstract We have studied the influence of an externally applied magnetic field on the photon and dark count rates of meander-type niobium nitride superconducting nanowire single-photon detectors. Measurements have been performed at a temperature of 4.2 K, and magnetic fields up to 250 mT have been applied perpendicularly to the meander plane. While photon count rates are field independent at weak applied fields, they show a strong dependence at fields starting from approximately ±25 mT. This behavior, as well as the magnetic field dependence of the dark count rates, is in good agreement with the recent theoretical model of vortex-assisted photon detection and spontaneous vortex crossing in narrow superconducting lines. However, the local reduction of the superconducting free energy due to photon absorption, which is the fitting parameter in the model, increases much slower with the photon energy than the model predicts. Furthermore, changes in the free-energy during photon counts and dark counts depend differently on the current that flows through the meander. This indicates that photon counts and dark counts occur in different parts of the meander.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1367
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Author Glejm, A. V.; Anisimov, A. A.; Asnis, L. N.; Vakhtomin, Yu. B.; Divochiy, A. V.; Egorov, V. I.; Kovalyuk, V. V.; Korneev, A. A.; Kynev, S. M.; Nazarov, Yu. V.; Ozhegov, R. V.; Rupasov, A. V.; Smirnov, K. V.; Smirnov, M. A.; Goltsman, G. N.; Kozlov, S. A.
Title Quantum key distribution in an optical fiber at distances of up to 200 km and a bit rate of 180 bit/s Type Journal Article
Year 2014 Publication Bulletin of the Russian Academy of Sciences. Physics Abbreviated Journal
Volume 78 Issue (up) 3 Pages 171-175
Keywords SSPD, SNSPD, applications
Abstract An experimental demonstration of a subcarrier-wave quantum cryptography system with superconducting single-photon detectors (SSPDs) that distributes a secure key in a single-mode fiber at distance of 25 km with a bit rate of 800 kbit/s, a distance of 100 km with a bit rate of 19 kbit/s, and a distance of 200 km with a bit rate of 0.18 kbit/s is described.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1062-8738 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ kovalyuk @ Serial 940
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Author Lusche, R.; Semenov, A.; Ilin, K.; Siegel, M.; Korneeva, Y.; Trifonov, A.; Korneev, A.; Goltsman, G.; Vodolazov, D.; Hübers, H.-W.
Title Effect of the wire width on the intrinsic detection efficiency of superconducting-nanowire single-photon detectors Type Journal Article
Year 2014 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 116 Issue (up) 4 Pages 043906 (1 to 9)
Keywords NbN SSPD, SNSPD, TaN
Abstract A thorough spectral study of the intrinsic single-photon detection efficiency in superconducting TaN and NbN nanowires with different widths has been performed. The experiment shows that the cut-off of the intrinsic detection efficiency at near-infrared wavelengths is most likely controlled by the local suppression of the barrier for vortex nucleation around the absorption site. Beyond the cut-off quasi-particle diffusion in combination with spontaneous, thermally activated vortex crossing explains the detection process. For both materials, the reciprocal cut-off wavelength scales linearly with the wire width where the scaling factor agrees with the hot-spot detection model.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1357
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Author Lobanov, Yury; Shcherbatenko, Michael; Shurakov, Alexander; Rodin, Alexander V.; Klimchuk, Artem; Nadezhdinsky, Alexander I.; Maslennikov, Sergey; Larionov, Pavel; Finkel, Matvey; Semenov, Alexander; Verevkin, Aleksandr A.; Voronov, Boris M.; Ponurovsky, Yakov; Klapwijk, Teunis M.; Gol'tsman, Gregory N.
Title Heterodyne detection at near-infrared wavelengths with a superconducting NbN hot-electron bolometer mixer Type Journal Article
Year 2014 Publication Opt. Lett. Abbreviated Journal
Volume 39 Issue (up) 6 Pages 1429-1432
Keywords HEB, zebra, IR, infrared
Abstract We report on the development of a highly sensitive optical receiver for heterodyne IR spectroscopy at the communication wavelength of 1.5 μm (200 THz) by use of a superconducting hot-electron bolometer. The results are important for the resolution of narrow spectral molecular lines in the near-IR range for the study of astronomical objects, as well as for quantum optical tomography and fiber-optic sensing. Receiver configuration as well as fiber-to-detector light coupling designs are discussed. Light absorption of the superconducting detectors was enhanced by nano-optical antennas, which were coupled to optical fibers. An intermediate frequency (IF) bandwidth of about 3 GHz was found in agreement with measurements at 300 GHz, and a noise figure of about 25 dB was obtained that was only 10 dB above the quantum limit.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 906
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Author Gurovich, B. A.; Tarkhov, M. A.; Prikhod'ko, K. E.; Kuleshova, E. A.; Komarov, D. A.; Stolyarov, V. L.; Olshanskii, E. D.; Goncharov, B. V.; Goncharova, D. A.; Kutuzov, L. V.; Domantovskii, A. G.
Title Controlled modification of superconducting properties of NbN ultrathin films under composite ion beam irradiation Type Journal Article
Year 2014 Publication Nanotechnologies in Russia Abbreviated Journal Nanotechnologies in Russia
Volume 9 Issue (up) 7 Pages 386-390
Keywords superconducting NbN films composite ion beam irradiation protoning
Abstract In this work, the results of studying the microstructure and superconducting properties of ultrathin films on the basis of NbN in the initial state and after modification by being subjecting to composite ion beam irradiation with the energy ~1–3) keV are presented. HRTEM analysis showed that the initial films on the sapphire substrate in orientation “c-cut” are characterized by a grain size essentially exceeding the film thickness, while on the other substrates the size of grains corresponds to the thickness of film. Using XPS analysis, it was shown that in the initial films the atomic ratio of Nb and N is 0.51/0.49, respectively, the percentage of oxygen being lower than 5%. For ultrathin films 5 nm in thickness, the critical temperature of transit to superconducting state (T c) is found to be ~3.6 K and the density of critical current is jc ~8MA/cm2. In the work it is experimentally determined that the irradiation of NbN films by composite ion beams leads to the controlled modification of its superconducting properties due to the process of selective substitution of nitrogen atoms on the oxygen atoms.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1000
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