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| Author | Beebe, M. R.; Beringer, D. B.; Burton, M. C.; Yang, K.; Lukaszew, R. A. | ||||
| Title | Stoichiometry and thickness dependence of superconducting properties of niobium nitride thin films | Type | Journal Article | ||
| Year | 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 Volume | Series Issue | Edition | |||
| ISSN | 0734-2101 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Potential plagiarism for 1503 | Approved | no | ||
| Call Number | Serial | 1504 | |||
| Permanent link to this record | |||||
| Author | Larrey, V.; Villegier, J. -C.; Salez, M.; Miletto-Granozio, F.; Karpov, A. | ||||
| Title | Processing and characterization of high Jc NbN superconducting tunnel junctions for THz analog circuits and RSFQ | Type | Journal Article | ||
| Year | 1999 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | |
| Volume | 9 | Issue | 2 | Pages | 3216-3219 |
| Keywords |
RSFQ, NbN, SIS | ||||
| Abstract | A generic NbN Superconducting Tunnel Junctions (STJ) technology has been developed using conventional substrates (Si and SOI-SIMOX) for making THz spectrometers including SIS receivers and RSFQ logic gates. NbN/MgO/NbN junctions with area of 1 /spl mu/m/sup 2/, Jc of 10 kA/cm/sup 2/ and low sub-gap leakage current (Vm>25 mV) are currently obtained from room temperature sputtered multilayers followed by a post-annealing at 250/spl deg/C. Using a thin MgO buffer layer deposited underneath the NbN electrodes, ensures lower NbN surface resistance values (Rs=7 /spl mu//spl Omega/) at 10 GHz and 4 K. Epitaxial NbN [100] films on MgO [100] with high gap frequency (1.4 THz) have also been achieved under the same deposition conditions at room temperature. The NbN SIS has shown good I-V photon induced steps when LO pumped at 300 GHz. We have developed an 8 levels Al/NbN multilayer process for making 1.5 THz SIS mixers (including Al antennas) on Si membranes patterned in SOI-SIMOX. Using the planarization techniques developed at the Si-MOS CEA-LETI Facility, we have also demonstrated on the possibility of extending our NbN technology to high level RSFQ circuit integration with 0.5 /spl mu/m/sup 2/ junction area, made on large area substrates (up to 8 inches). | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1081 | |||
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| Author | Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Yngvesson, K. S. | ||||
| Title | Hot electron bolometer detectors and mixers based on a superconducting-two-dimensional electron gas-superconductor structure | Type | Conference Article | ||
| Year | 1997 | Publication | Proc. 4-th Int. Semicond. Device Research Symp. | Abbreviated Journal | Proc. 4-th Int. Semicond. Device Research Symp. |
| Volume | Issue | Pages | 163-166 | ||
| Keywords |
S-2DEG-S HEB mixers, detectors, AlGaAs/GaAs heterostructures, NbN | ||||
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1603 | |||
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| Author | Pentin, I. V.; Smirnov, A. V.; Ryabchun, S. A.; Ozhegov, R. V.; Gol’tsman, G. N.; Vaks, V. L.; Pripolzin, S. I.; Pavel’ev, D. G.; Koshurinov, Y. I.; Ivanov, A. S. | ||||
| Title | Semiconducting superlattice as a solid-state terahertz local oscillator for NbN hot-electron bolometer mixers | Type | Journal Article | ||
| Year | 2012 | Publication | Tech. Phys. | Abbreviated Journal | Tech. Phys. |
| Volume | 57 | Issue | 7 | Pages | 971-974 |
| Keywords |
semiconducting superlattice frequency multiplier, NbN HEB mixers | ||||
| Abstract | We present the results of our studies of the semiconducting superlattice (SSL) frequency multiplier and its application as part of the solid state local oscillator (LO) in the terahertz heterodyne receiver based on a NbN hot-electron bolometer (HEB) mixer. We show that the SSL output power level increases as the ambient temperature is lowered to 4.2 K, the standard HEB operation temperature. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1063-7842 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1378 | |||
| Permanent link to this record | |||||
| Author | Sidorova, M.; Semenov, A.; Hübers, H.-W.; Kuzmin, A.; Doerner, S.; Ilin, K.; Siegel, M.; Charaev, I.; Vodolazov, D. | ||||
| Title | Timing jitter in photon detection by straight superconducting nanowires: Effect of magnetic field and photon flux | Type | Journal Article | ||
| Year | 2018 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
| Volume | 98 | Issue | 13 | Pages | 134504 (1 to 14) |
| Keywords |
SNSPD, NbN namowires | ||||
| Abstract | We studied the effects of the external magnetic field and photon flux on timing jitter in photon detection by straight superconducting NbN nanowires. At two wavelengths 800 and 1560 nm, statistical distribution in the appearance times of photon counts exhibits Gaussian shape at small times and an exponential tail at large times. The characteristic exponential time is larger for photons with smaller energy and increases with external magnetic field while variations in the Gaussian part of the distribution are less pronounced. Increasing photon flux drives the nanowire from the discrete quantum detection regime to the uniform bolometric regime that averages out fluctuations of the total number of nonequilibrium electrons created by the photon and drastically reduces jitter. The difference between standard deviations of Gaussian parts of distributions for these two regimes provides the measure for the strength of electron-number fluctuations; it increases with the photon energy. We show that the two-dimensional hot-spot detection model explains qualitatively the effect of magnetic field. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1842 | |||
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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. | ||||
| Title | On the measurement of intensity correlations from laboratory and astronomical sources with SPADs and SNSPDs | Type | Conference Article | ||
| Year | 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. | ||||
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| Publisher | SPIE | Place of Publication | Editor | Malbet, F.; Creech-Eakman, M.J.; Tuthill, P.G. | |
| Language | Summary Language | Original Title | |||
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| Area | Expedition | Conference | Optical and Infrared Interferometry and Imaging V | ||
| Notes | Approved | no | |||
| Call Number | Serial | 1809 | |||
| Permanent link to this record | |||||
| Author | Henrich, D.; Dorner,S.; Hofherr, M.; Il'in, K.; Semenov, A.; Heintze, E.; Scheffler, M.; Dressel, M.; Siegel, M. | ||||
| Title | Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content | Type | Journal Article | ||
| Year | 2012 | Publication | Abbreviated Journal | J. Appl. Phys. | |
| Volume | 112 | Issue | Pages | ||
| Keywords |
SSPD, SNSPD, magnetron sputtering, spectrum, NbN film, nitrogen concentration | ||||
| Abstract | The spectral detection efficiency and the dark count rate of superconducting nanowire single-photon detectors (SNSPD) have been studied systematically on detectors made from thin NbN films with different chemical compositions. Reduction of the nitrogen content in the 4 nm thick NbN films results in a decrease of the dark count rates more than two orders of magnitude and in a red shift of the cut-off wavelength of the hot-spot SNSPD response. The observed phenomena are explained by an improvement of uniformity of NbN films that has been confirmed by a decrease of resistivity and an increase of the ratio of the measured critical current to the depairing current. The latter factor is considered as the most crucial for both the cut-off wavelength and the dark count rates of SNSPD. Based on our results we propose a set of criteria for material properties to optimize SNSPD in the infrared spectral region. VC 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4757625] |
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| Corporate Author | D. Henrich, S. Dorner, M. Hofherr, K. Il'in, A. Semenov, E. Heintze, M. Scheffler, M. Dressel, M. Siegel | Thesis | |||
| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ seleznev @ | Serial | 877 | ||
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| Author | Kovalyuk, V.; Hartmann, W.; Kahl, O.; Kaurova, N.; Korneev, A.; Goltsman, G.; Pernice, W. H. P. | ||||
| Title | Absorption engineering of NbN nanowires deposited on silicon nitride nanophotonic circuits | Type | Journal Article | ||
| Year | 2013 | Publication | Opt. Express | Abbreviated Journal | Opt. Express |
| Volume | 21 | Issue | 19 | Pages | 22683-22692 |
| Keywords |
SSPD, SNSPD, NbN nanoeires, Si3N4 waveguides | ||||
| Abstract | We investigate the absorption properties of U-shaped niobium nitride (NbN) nanowires atop nanophotonic circuits. Nanowires as narrow as 20nm are realized in direct contact with Si3N4 waveguides and their absorption properties are extracted through balanced measurements. We perform a full characterization of the absorption coefficient in dependence of length, width and separation of the fabricated nanowires, as well as for waveguides with different cross-section and etch depth. Our results show excellent agreement with finite-element analysis simulations for all considered parameters. The experimental data thus allows for optimizing absorption properties of emerging single-photon detectors co-integrated with telecom wavelength optical circuits. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1094-4087 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:24104155 | Approved | no | ||
| Call Number | Serial | 1213 | |||
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| Author | Korneev, A.; Minaeva, O.; Divochiy, A.; Antipov, A.; Kaurova, N.; Seleznev, V.; Voronov, B.; Gol’tsman, G.; Pan, D.; Kitaygorsky, J.; Slysz, W.; Sobolewski, R. | ||||
| Title | Ultrafast and high quantum efficiency large-area superconducting single-photon detectors | Type | Conference Article | ||
| Year | 2007 | Publication | Proc. SPIE | Abbreviated Journal | Proc. SPIE |
| Volume | 6583 | Issue | Pages | 65830I (1 to 9) | |
| Keywords |
SSPD, SNSPD, superconducting NbN films, infrared single-photon detectors | ||||
| Abstract | We present our latest generation of superconducting single-photon detectors (SSPDs) patterned from 4-nm-thick NbN films, as meander-shaped 0.5-mm-long and 100-nm-wide stripes. The SSPDs exhibit excellent performance parameters in the visible-to-near-infrared radiation wavelengths: quantum efficiency (QE) of our best devices approaches a saturation level of 30% even at 4.2 K (limited by the NbN film optical absorption) and dark counts as low as 2x10-4 Hz. The presented SSPDs were designed to maintain the QE of large-active-area devices, but, unless our earlier SSPDs, hampered by a significant kinetic inductance and a nanosecond response time, they are characterized by a low inductance and GHz counting rates. We have designed, simulated, and tested the structures consisting of several, connected in parallel, meander sections, each having a resistor connected in series. Such new, multi-element geometry led to a significant decrease of the device kinetic inductance without the decrease of its active area and QE. The presented improvement in the SSPD performance makes our detectors most attractive for high-speed quantum communications and quantum cryptography applications. | ||||
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| Publisher | Spie | Place of Publication | Editor | Dusek, M.; Hillery, M.S.; Schleich, W.P.; Prochazka, I.; Migdall, A.L.; Pauchard, A. | |
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| Notes | Approved | no | |||
| Call Number | Serial | 1249 | |||
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| Author | Maslennikov, S. | ||||
| Title | RF heating efficiency of the terahertz superconducting hot-electron bolometer | Type | Journal Article | ||
| Year | 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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| Notes | Approved | no | |||
| Call Number | RPLAB @ atomics90 @ | Serial | 954 | ||
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