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Author Arutyunov, K. Y.; Ramos-Álvarez, A.; Semenov, A. V.; Korneeva, Y. P.; An, P. P.; Korneev, A. A.; Murphy, A.; Bezryadin, A.; Gol’tsman, G. N. url  openurl
  Title Quasi-1-dimensional superconductivity in highly disordered NbN nanowires Type Miscellaneous
  Year (down) 2016 Publication arXiv Abbreviated Journal  
  Volume Issue Pages  
  Keywords narrow NbN nanowires, BCS  
  Abstract The topic of superconductivity in strongly disordered materials has attracted a significant attention. In particular vivid debates are related to the subject of intrinsic spatial inhomogeneity responsible for non-BCS relation between the superconducting gap and the pairing potential. Here we report experimental study of electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. We find that conventional models based on phase slip concept provide reasonable fits for the shape of the R(T) transition curve. Temperature dependence of the critical current follows the text-book Ginzburg-Landau prediction for quasi-one-dimensional superconducting channel Ic~(1-T/Tc)^3/2. Hence, one may conclude that the intrinsic electronic inhomogeneity either does not exist in our structures, or, if exist, does not affect their resistive state properties.  
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  Corporate Author Thesis  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Duplicated as 1332 Approved no  
  Call Number Serial 1338  
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Author Korneeva, Y.; Sidorova, M.; Semenov, A.; Krasnosvobodtsev, S.; Mitsen, K.; Korneev, A.; Chulkova, G.; Goltsman, G. url  doi
openurl 
  Title Comparison of hot-spot formation in NbC and NbN single-photon detectors Type Journal Article
  Year (down) 2016 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 26 Issue 3 Pages 1-4  
  Keywords NbC, NbN SSPD, SNSPD  
  Abstract We report an experimental investigation of the hot-spot evolution in superconducting single-photon detectors made of disordered superconducting materials with different diffusivity and energy downconversion time values, i.e., 33-nm-thick NbN and 23-nm-thick NbC films. We have demonstrated that, in NbC film, only 405-nm photons produce sufficiently large hot spot to trigger a single-photon response. The dependence of detection efficiency on bias current for 405-nm photons in NbC is similar to that for 3400-nm photons in NbN. In NbC, large diffusivity and downconversion time result in 1-D critical current suppression profile compared with the usual 2-D profile in NbN.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1051-8223 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1348  
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Author Beebe, M. R.; Beringer, D. B.; Burton, M. C.; Yang, K.; Lukaszew, R. A. url  doi
openurl 
  Title Stoichiometry and thickness dependence of superconducting properties of niobium nitride thin films Type Journal Article
  Year (down) 2016 Publication Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films Abbreviated Journal Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films  
  Volume 34 Issue 2 Pages 021510 (1 to 4)  
  Keywords potential plagiarism, possible plagiarism, NbN films  
  Abstract The current technology used in linear particle accelerators is based on superconducting radio frequency (SRF) cavities fabricated from bulk niobium (Nb), which have smaller surface resistance and therefore dissipate less energy than traditional nonsuperconducting copper cavities. Using bulk Nb for the cavities has several advantages, which are discussed elsewhere; however, such SRF cavities have a material-dependent accelerating gradient limit. In order to overcome this fundamental limit, a multilayered coating has been proposed using layers of insulating and superconducting material applied to the interior surface of the cavity. The key to this multilayered model is to use superconducting thin films to exploit the potential field enhancement when these films are thinner than their London penetration depth. Such field enhancement has been demonstrated in MgB2 thin films; here, the authors consider films of another type-II superconductor, niobium nitride (NbN). The authors present their work correlating stoichiometry and superconducting properties in NbN thin films and discuss the thickness dependence of their superconducting properties, which is important for their potential use in the proposed multilayer structure. While there are some previous studies on the relationship between stoichiometry and critical temperature TC, the authors are the first to report on the correlation between stoichiometry and the lower critical field HC1.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0734-2101 ISBN Medium  
  Area Expedition Conference  
  Notes Potential plagiarism for 1503 Approved no  
  Call Number Serial 1504  
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Author Schroeder, E.; Mauskopf, P.; Pilyavsky, G.; Sinclair, A.; Smith, N.; Bryan, S.; Mani, H.; Morozov, D.; Berggren, K.; Zhu, D.; Smirnov, K.; Vakhtomin, Y. url  doi
openurl 
  Title On the measurement of intensity correlations from laboratory and astronomical sources with SPADs and SNSPDs Type Conference Article
  Year (down) 2016 Publication Proc. SPIE Abbreviated Journal Proc. SPIE  
  Volume 9907 Issue Pages 99070P (1 to 13)  
  Keywords SPAD, NbN SSPD applications, SNSPD  
  Abstract We describe the performance of detector modules containing silicon single photon avalanche photodiodes (SPADs) and superconducting nanowire single photon detectors (SNSPDs) to be used for intensity interferometry. The SPADs are mounted in fiber-coupled and free-space coupled packages. The SNSPDs are mounted in a small liquid helium cryostat coupled to single mode fiber optic cables which pass through a hermetic feed-through. The detectors are read out with microwave amplifiers and FPGA-based coincidence electronics. We present progress on measurements of intensity correlations from incoherent sources including gas-discharge lamps and stars with these detectors. From the measured laboratory performance of the correlation system, we estimate the sensitivity to intensity correlations from stars using commercial telescopes and larger existing research telescopes.  
  Address  
  Corporate Author Thesis  
  Publisher SPIE Place of Publication Editor Malbet, F.; Creech-Eakman, M.J.; Tuthill, P.G.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference Optical and Infrared Interferometry and Imaging V  
  Notes Approved no  
  Call Number Serial 1809  
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Author Zolotov, P. I.; Vakhtomin, Yu. B.; Divochiy, A. V.; Seleznev, V. A.; Smirnov, K. V. url  isbn
openurl 
  Title Technology development of resonator-based structures for efficiency increasing of NBN detectors of IR single photons Type Journal Article
  Year (down) 2016 Publication Proc. 5th Int. Conf. Photonics and Information Optics Abbreviated Journal Proc. 5th Int. Conf. Photonics and Information Optics  
  Volume Issue Pages 115-116  
  Keywords NbN SSPD  
  Abstract This paper presents a technology of fabrication of NbN superconductive single- photon detectors, using resonator structures. The main results are related to optimization of the process of NbN sputtering over substrate with metallic mirrors and SiO 2 /Si 3 N 4 layers /4 thick. Investigation of the quantum efficiency of fabricated devices at 1.6 K on 1.55 μm showed triple-magnified value compared to standard Si/NbN structures.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Russian Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-5-7262-2215-8 Medium  
  Area Expedition Conference  
  Notes http://fioconf.mephi.ru/files/2015/12/FIO2016-Sbornik.pdf Разработка технологии создания резонаторных структур для увеличения квантовой эффективности NBN детекторов ИК-фотонов Approved no  
  Call Number Serial 1811  
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Author Trifonov, A.; Tong, C.-Y. E.; Blundell, R.; Ryabchun, S.; Gol'tsman, G. url  doi
openurl 
  Title Probing the stability of HEB mixers with microwave injection Type Journal Article
  Year (down) 2015 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 25 Issue 3 Pages 2300404 (1 to 4)  
  Keywords NbN HEB mixer, stability, Allan-variance  
  Abstract Using a microwave probe as a tool, we have performed experiments aimed at understanding the origin of the output-power fluctuations in hot-electron-bolometer (HEB) mixers. We use a probe frequency of 1.5 GHz. The microwave probe picks up impedance changes of the HEB, which are examined upon demodulation of the reflected wave outside the cryostat. This study shows that the HEB mixer operates in two different regimes under a terahertz pump. At a low pumping level, strong pulse modulation is observed, as the device switches between the superconducting state and the normal state at a rate of a few megahertz. When pumped much harder, to approximate the low-noise mixer operating point, residual modulation can still be observed, showing that the HEB mixer is intrinsically unstable even in the resistive state. Based on these observations, we introduced a low-frequency termination to the HEB mixer. By terminating the device in a 50-Ω resistor in the megahertz frequency range, we have been able to improve the output-power Allan time of our HEB receiver by a factor of four to about 10 s for a detection bandwidth of 15 MHz, with a corresponding gain fluctuation of about 0.035%.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1051-8223 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1355  
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Author Tretyakov, I.; Maslennikov, S.; Semenov, A.; Safir, O.; Finkel, M.; Ryabchun, S.; Kaurova, N.; Voronov, B.; Goltsman, G.; Klapwijk, T. M. url  openurl
  Title Impact of operating conditions on noise and gain bandwidth of NbN HEB mixers Type Conference Article
  Year (down) 2015 Publication Proc. 26th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 26th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 39  
  Keywords NbN HEB mixers  
  Abstract Hot-electron bolometer mixers (HEB’s) are the most promising devices as mixing element for terahertz spectroscopy and astronomy at frequencies beyond 1.4 THz. They have a low noise temperature and low demands on local oscillator (LO) power. 1,2 An important limitation is the IF bandwidth, of the order of a few GHz, and which in principle depends on energy relaxation due to electron- phonon processes and on diffusion-cooling. It has been proposed by Prober that a reduction in length of the HEB would lead to an increased bandwidth. 3 This appeared to be achieved by Tretyakov et al by measuring the gain bandwidth close to the critical temperature of the NbN. 2 Unfortunately, the noise bandwidth of similar devices operated at temperatures around 4.2 K appear not depend on the length. The fundamental problem to be addressed is the position-dependent superconducting state of the HEB- devices under operating conditions, which determines the conditions for the cooling of the hot quasiparticles. Some progress has been made by Barends et al in a semi-empirical model to describe the I,V curves under operating conditions at a bath temperature around 4.2 K. 4 In more recent work Vercruyssen et al have analyzed the I,V curve, without any LO-equivalent bias, of a model NSN system. 5 This work suggests that the most appropriate model for an HEB under operating conditions is that of a potential-well in the superconducting gap in the center of the NbN, analogous the bimodal superconducting state described by Vercruyssen et al. Hot quasiparticles in the well can not diffuse out and can only cool by electron-phonon processes, those with higher energies than the heights of the walls of the well can diffuse out. Using this working hypothesis we have carried out experiments on a sub-micrometer NbN bridge connected to a gold (Au) planar spiral antenna. An in situ process is used to deposit Au on NbN. The Au is removed in the center to define the uncovered NbN, which will act as the superconducting mixer itself. The antenna is deposited on the remaining Au layer on the NbN. The Au contacts suppress the energy gap of the NbN film located underneath the gold layer 7,8 . The measured resistive transition is shown in Fig.1. It clearly shows a T c of the bilayer at 6.2 K and the resistive transition of the NbN itself around 9 K. In addition we show the measured noise bandwidth (red squares) for different bath temperatures. Clearly the noise bandwidth increases strongly by increasing the bath temperature from 5 K to 8 K, up to 13 GHz. We interpret this pattern as evidence for improved out-diffusion of hot electrons due to normal banks and a shallow superconducting potential well compared to k B T. As expected the noise temperature in this regime is much bigger than when biased at 4.2 K. R EFERENCES 1 W. Zhang, P. Khosropanah, J. R. Gao, E. L. Kollberg, K. S. Yngvesson, T. Bansal, R. Barends, and T. M. Klapwijk Appl. Phys. Lett. 96, 111113, (2010). 2 Ivan Tretyakov, Sergey Ryabchun, Matvey Finkel, Anna Maslennikova, Natalia Kaurova, Anastasia Lobastova, Boris Voronov, and Gregory Gol’tsman Appl. Phys. Lett. 98, 033507 (2011). 3 D. E. Prober, Appl. Phys. Lett. 62, 2119 (1992). 4 R. Barends, M. Hajenius, J. R. Gao, and T. M. Klapwijk, Appl. Phys. Lett. 87, 263506 (2005). 5 N. Vercruyssen, T. G. A. Verhagen, M. G. Flokstra, J. P. Pekola, and T. M. Klapwijk Physical Review B 85, 224503 (2012).  
  Address  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1159  
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Author Tong, C.-Y. E.; Trifonov, A.; Shurakov, A.; Blundell, R.; Gol’tsman, G. url  doi
openurl 
  Title A microwave-operated hot-electron-bolometric power detector for terahertz radiation Type Journal Article
  Year (down) 2015 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 25 Issue 3 Pages 2300604 (1 to 4)  
  Keywords NbN HEB mixer  
  Abstract A new class of microwave-operated THz power detectors based on the NbN hot-electron-bolometer (HEB) mixer is proposed. The injected microwave signal ( 1 GHz) serves the dual purpose of pumping the HEB element and enabling the read-out of the internal state of the device. A cryogenic amplifier amplifies the reflected microwave signal from the device and a homodyne scheme recovers the effects of the incident THz radiation. Two modes of operation have been identified, depending on the level of incident radiation. For weak signals, we use a chopper to chop the incident radiation against a black body reference and a lock-in amplifier to perform synchronous detection of the homodyne readout. The voltage measured is proportional to the incident power, and we estimate an optical noise equivalent power of  5pW/ √Hz at 0.83 THz. At higher signal levels, the homodyne circuit recovers the stream of steady relaxation oscillation pulses from the HEB device. The frequency of these pulses is in the MHz frequency range and bears a linear relationship with the incident THz radiation over an input power range of  15 dB. A digital frequency counter is used to measure THz power. The applicable power range is between 1 nW and 1 μW.  
  Address  
  Corporate Author Thesis  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1558-2515 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1354  
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Author Корнеев, А. А.; Окунев, О. В.; Чулкова, Г. М.; Смирнов, К. В.; Милостная, И. И.; Минаева, О. В.; Корнеева, Ю. П.; Каурова, Н. С.; Воронов, Б. М.; Гольцман, Г. Н. isbn  openurl
  Title Спонтанные и фотоиндуцированные резистивные состояния в узких сверхпроводящих NbN полосках Type Book Whole
  Year (down) 2015 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords NbN films  
  Abstract Монография посвящена актуальной проблеме современной фотоники: разработке высокочувствительных и быстродействующих сверхпроводниковых однофотонных детекторов на основе тонкой пленки NbN. В работе исследуются неравновесные процессы, протекающие в тонкой сверхпроводящей пленке после поглощения инфракрасного фотона и приводящие к возникновению резистивного состояния. На этих процессах основан механизм фотоотклика исследуемого в работе однофотонного детектора. В частности, исследуются зависимости квантовой эффективности и скорости темнового счета от геометрических параметров детектора: толщины пленки, ширины полоски, а также от величины транспортного тока детектора. Монография предназначена для студентов старших курсов, аспирантов и начинающих исследователей, работающих в области сверхпроводниковой наноэлектроники и радиофизики.  
  Address Москва  
  Corporate Author Thesis  
  Publisher МПГУ Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-5-4263-0269-3 Medium  
  Area Expedition Conference  
  Notes УДК: 535; Число страниц: 108 Approved no  
  Call Number Serial 1812  
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Author Smirnov, K.; Vachtomin, Y.; Divochiy, A.; Antipov, A.; Goltsman, G. url  openurl
  Title The limitation of noise equivalent power by background radiation for infrared superconducting single photon detectors coupled to standard single mode optical fibers Type Journal Article
  Year (down) 2015 Publication Rus. J. Radio Electron. Abbreviated Journal Rus. J. Radio Electron.  
  Volume Issue 5 Pages  
  Keywords NbN SSPD  
  Abstract We investigated the minimum level of the dark count rates and noise equivalent power of superconducting single photon detectors coupled to standard single mode optical fibers. We found that background radiation limits the minimum level of the dark count rates. We also proposed the effective method for reducing background radiation out of the required spectral range of the detector. Measured noise equivalent power of detector reaches 8.9×10-19 W×Hz1/2 at a wavelength of 1.55 μm and quantum efficiency 35%.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  Area Expedition Conference  
  Notes 14 pages Approved no  
  Call Number Serial 1813  
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Author Miao, W.; Zhang, W.; Zhong, J. Q.; Shi, S. C.; Delorme, Y.; Lefevre, R.; Feret, A; Vacelet, T url  doi
openurl 
  Title Non-uniform absorption of terahertz radiation on superconducting hot electron bolometer microbridges Type Journal Article
  Year (down) 2014 Publication Appl. Phys. Lett. Abbreviated Journal <ef><bf><bc>Appl. Phys. Lett.  
  Volume 104 Issue Pages 052605(1-4)  
  Keywords NbN HEB mixers, local oscillator power, RF nonuniform absorption  
  Abstract We interpret the experimental observation of a frequency-dependence of superconducting hot electron bolometer (HEB) mixers by taking into account the non-uniform absorption of the terahertz radiation on the superconducting HEB microbridge. The radiation absorption is assumed to be proportional to the local surface resistance of the HEB microbridge, which is computed using the Mattis-Bardeen theory. With this assumption the dc and mixing characteristics of a superconducting niobium-nitride (NbN) HEB device have been modeled at frequencies below and above the equilibrium gap frequency of the NbN film.  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 935  
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Author Maslennikov, S. url  openurl
  Title RF heating efficiency of the terahertz superconducting hot-electron bolometer Type Journal Article
  Year (down) 2014 Publication arXiv Abbreviated Journal arXiv  
  Volume 1404.5276 Issue Pages 1-4  
  Keywords superconducting hot-electron bolometer mixer, HEB, NbN, distributed model, HEB model, HEB mixer model, heat balance equa-tions, conversion gain, RF heating efficiency, noise temperature, simulation, Euler method  
  Abstract We report results of the numerical solution by the Euler method of the system of heat balance equations written in recurrent form for the superconducting hot-electron bolometer (HEB) embedded in an electrical circuit. By taking into account the dependence of the HEB resistance on the transport current we have been able to calculate rigorously the RF heating efficiency, absorbed local oscillator (LO) power and conversion gain of the HEB mixer. We show that the calculated conversion gai nis in excellent agreement with the experimental results, and that the substitution of the calculated RF heating efficiency and absorbed LO power into the expressions for the conversion gain and noise temperature given by the analytical small-signal model of the HEB yields excellent agreement with the corresponding measured values  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number RPLAB @ atomics90 @ Serial 954  
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Author Zhang, W.; Miao, W.; Zhong, J. Q.; Shi, S. C.; Hayton, D. J.; Vercruyssen, N.; Gao, J. R.; Goltsman, G. N. url  doi
openurl 
  Title Temperature dependence of the receiver noise temperature and IF bandwidth of superconducting hot electron bolometer mixers Type Journal Article
  Year (down) 2014 Publication Supercond. Sci. Technol. Abbreviated Journal Supercond. Sci. Technol.  
  Volume 27 Issue 8 Pages 085013 (1 to 5)  
  Keywords NbN HEB mixers  
  Abstract In this paper we study the temperature dependence of the receiver noise temperature and IF noise bandwidth of superconducting hot electron bolometer (HEB) mixers. Three superconducting NbN HEB devices of different transition temperatures (Tc) are measured at 0.85 THz and 1.4 THz at different bath temperatures (Tbath) between 4 K and 9 K. Measurement results demonstrate that the receiver noise temperature of superconducting NbN HEB devices is nearly constant for Tbath/Tc, less than 0.8, which is consistent with the simulation based on a distributed hot-spot model. In addition, the IF noise bandwidth appears independent of Tbath/Tc, indicating the dominance of phonon cooling in the investigated HEB devices.  
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  Series Volume Series Issue Edition  
  ISSN 0953-2048 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1358  
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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. openurl 
  Title Controlled modification of superconducting properties of NbN ultrathin films under composite ion beam irradiation Type Journal Article
  Year (down) 2014 Publication Nanotechnologies in Russia Abbreviated Journal Nanotechnologies in Russia  
  Volume 9 Issue 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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  Notes Approved no  
  Call Number Serial 1000  
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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. url  doi
openurl 
  Title Effect of the wire width on the intrinsic detection efficiency of superconducting-nanowire single-photon detectors Type Journal Article
  Year (down) 2014 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.  
  Volume 116 Issue 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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  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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