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| Author | Омельянук, А. Н.; Ильичев, Е. В.; Шевченко, С. Н. | ||||
| Title | Квантовые когерентные явления в джозефсоновских кубитах | Type | Book Whole | ||
Year  |
2013 | Publication | Наукова думка | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | Josephson qubit, quantum computer, Rabi cycle, Landau-Zener effect, multiphoton transitions, single qubits | ||||
| Abstract | Монография посвящена актуальным проблемам физики сверхпроводниковых джозефсоновских кубитов — макроскопических квантовых структур, перспективных элементов квантовых компьютеров. Приведены элементы квантовой механики кубитов, фундаментальные свойства сверхпроводников, физика классических и квантовых джозефсоновских структур. Рассмотрены основные типы сверхпроводниковых кубитов. Изложены результаты экспериментальных и теоретических исследований квантовых когерентных явлений в джозефсоновских кубитах. Рассмотрены спектроскопия энергетичеÂских состояний, осцилляции Раби, эффект Ландау-Зинера, многофотонные переходы в одиночних кубитах и в системах связанных кубитов. Изучено влияние шумов на потоковый кубит и на его классический аналог. Для специалистов в области теоретической и прикладной физики, сверхпроводниковой микроэлектроники, а также аспирантов и студентов физико-технических специальностей. |
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| Publisher | ФТИНТ им. Б. И. Верника НАН Украины | Place of Publication | Киев | Editor | |
| Language | Russian | Summary Language | Original Title | ||
| Series Editor | Series Title | Наукова книга | Abbreviated Series Title | ||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | 978-966-00-1260-8 | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Ссылку прислал Саша Семенов в [RpL 755]. | Approved | no | ||
| Call Number | Serial | 933 | |||
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| Author | Kardakova, A.; Finkel, M.; Morozov, D.; Kovalyuk, V.; An, P.; Dunscombe, C.; Tarkhov, M.; Mauskopf, P.; Klapwijk, T.M.; Goltsman, G. | ||||
| Title | The electron-phonon relaxation time in thin superconducting titanium nitride films | Type | Journal Article | ||
| Year |
2013 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 103 | Issue | 25 | Pages | 252602 (1 to 4) |
| Keywords | disordered TiN films, electron-phonon relaxation time | ||||
| Abstract | We report on the direct measurement of the electron-phonon relaxation time, τeph, in disordered TiN films. Measured values of τeph are from 5.5 ns to 88 ns in the 4.2 to 1.7 K temperature range and consistent with a T−3 temperature dependence. The electronic density of states at the Fermi level N0 is estimated from measured material parameters. The presented results confirm that thin TiN films are promising candidate-materials for ultrasensitive superconducting detectors. The work was supported by the Ministry of Education and Science of the Russian Federation, Contract No. 14.B25.31.0007 and by the RFBR Grant No. 13-02-91159. |
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | RPLAB @ kovalyuk @ | Serial | 941 | ||
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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 | Schuck, C.; Pernice, W. H. P.; Minaeva, O.; Li, Mo; Gol'tsman, G.; Sergienko, A. V.; Tang, H. X. | ||||
| Title | Matrix of integrated superconducting single-photon detectors with high timing resolution | Type | Journal Article | ||
| Year |
2013 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 23 | Issue | 3 | Pages | 2201007-2201007 |
| Keywords | NbN SSPD, SNSPD, array, matrix | ||||
| Abstract | We demonstrate a large grid of individually addressable superconducting single photon detectors on a single chip. Each detector element is fully integrated into an independent waveguide circuit with custom functionality at telecom wavelengths. High device density is achieved by fabricating the nanowire detectors in traveling wave geometry directly on top of silicon-on-insulator waveguides. Our superconducting single photon detector matrix includes detector designs optimized for high detection efficiency, low dark count rate, and high timing accuracy. As an example, we exploit the high timing resolution of a particularly short nanowire design to resolve individual photon round-trips in a cavity ring-down measurement of a silicon ring resonator. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1051-8223 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1373 | |||
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| Author | Lusche, Robert; Semenov, Alexey; Huebers, Heinz-Willhelm; Ilin, Konstantin; Siegel, Michael; Korneeva, Yuliya; Trifonov, Andrey; Korneev, Alexander; Goltsman, Gregory | ||||
| Title | Effect of the wire geometry and an externally applied magnetic field on the detection efficiency of superconducting nanowire single-photon detectors | Type | Abstract | ||
| Year |
2013 | Publication | INIS | Abbreviated Journal | INIS |
| Volume | 46 | Issue | 8 | Pages | 1-3 |
| Keywords | TaN, NbN SSPD, SNSPD | ||||
| Abstract | The interest in single-photon detectors in the near-infrared wavelength regime for applications, e.g. in quantum cryptography has immensely increased in the last years. Superconducting nanowire single-photon detectors (SNSPD) already show quite reasonable detection efficiencies in the NIR which can even be further improved. Novel theoretical approaches including vortex-assisted photon counting state that the detection efficiency in the long wavelength region can be enhanced by the detector geometry and an applied magnetic field. We present spectral measurements in the wavelength range from 350-2500 nm of the detection efficiency of meander-type TaN and NbN SNSPD with varying nanowire line width from 80 to 250 nm. Due to the used experimental setup we can accurately normalize the measured spectra and are able to extract the intrinsic detection efficiency (IDE) of our detectors. The results clearly indicate an improvement of the IDE depending on the wire width according to the theoretic models. Furthermore we experimentally found that the smallest detectable photon-flux can be increased by applying a small magnetic field to the detectors. | ||||
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1374 | |||
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| Author | Beck, M.; Rousseau, I.; Klammer, M.; Leiderer, P.; Mittendorff, M.; Winnerl, S.; Helm, M.; Gol'tsman, G.N.; Demsar, J. | ||||
| Title | Transient increase of the energy gap of superconducting NbN thin films excited by resonant narrow-band terahertz pulses | Type | Journal Article | ||
| Year |
2013 | Publication | Phys. Rev. Lett. | Abbreviated Journal | Phys. Rev. Lett. |
| Volume | 110 | Issue | 26 | Pages | 267003 (1 to 5) |
| Keywords | NbN thin films, energy gap | ||||
| Abstract | Observations of radiation-enhanced superconductivity have thus far been limited to a few type-I superconductors (Al, Sn) excited at frequencies between the inelastic scattering rate and the superconducting gap frequency 2Delta/h. Utilizing intense, narrow-band, picosecond, terahertz pulses, tuned to just below and above 2Delta/h of a BCS superconductor NbN, we demonstrate that the superconducting gap can be transiently increased also in a type-II dirty-limit superconductor. The effect is particularly pronounced at higher temperatures and is attributed to radiation induced nonthermal electron distribution persisting on a 100 ps time scale. | ||||
| Address | Department of Physics and Center for Applied Photonics, University of Konstanz, D-78457, Germany | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:23848912 | Approved | no | ||
| Call Number | Serial | 1370 | |||
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| Author | Korneev, A.; Korneeva, Y.; Manova, N.; Larionov, P.; Divochiy, A.; Semenov, A.; Chulkova, G.; Vachtomin, Y.; Smirnov, K.; Goltsman, G. | ||||
| Title | Recent nanowire superconducting single-photon detector optimization for practical applications | Type | Journal Article | ||
| Year |
2013 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 23 | Issue | 3 | Pages | 2201204 (1 to 4) |
| Keywords | SSPD, SNSPD | ||||
| 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. | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ akorneev @ KorneevIEEE2013 | Serial | 996 | ||
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| Author | Collins, M. J.; Xiong, C.; Rey, I. H.; Vo, T. D.; He, J.; Shahnia, S.; Reardon, C.; Krauss, T. F.; Steel, M. J.; Clark, M.J.; & Eggleton, B.J. | ||||
| Title | Integrated spatial multiplexing of heralded single-photon sources | Type | Journal Article | ||
| Year |
2013 | Publication | Nature Communications | Abbreviated Journal | |
| Volume | Issue | Pages | |||
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| Abstract | The non-deterministic nature of photon sources is a key limitation for single-photon quantum processors. Spatial multiplexing overcomes this by enhancing the heralded single-photon yield without enhancing the output noise. Here the intrinsic statistical limit of an individual source is surpassed by spatially multiplexing two monolithic silicon-based correlated photon pair sources in the telecommunications band, demonstrating a 62.4% increase in the her- alded single-photon output without an increase in unwanted multipair generation. We further demonstrate the scalability of this scheme by multiplexing photons generated in two waveguides pumped via an integrated coupler with a 63.1% increase in the heralded photon rate. This demonstration paves the way for a scalable architecture for multiplexing many photon sources in a compact integrated platform and achieving efficient two-photon inter- ference, required at the core of optical quantum computing and quantum communication protocols. | ||||
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| Language | English | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ alex_kazakov @ | Serial | 1001 | ||
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| Author | Zhang, Zijing; Zhang, Jianlong; Wu, Long; Zhang, Yong; Zhao, Yuan; Su, Jianzhong | ||||
| Title | Photon-counting chirped amplitude modulation lidar using a smart premixing method | Type | Journal Article | ||
| Year |
2013 | Publication | Opt. Lett. | Abbreviated Journal | Opt. Lett. |
| Volume | 38 | Issue | 21 | Pages | 4389-4392 |
| Keywords | photon-counting detector, lidar, Geiger mode APD, Geiger mode lidar | ||||
| Abstract | We proposed a new premixing method for photon-counting chirped amplitude modulation lidar (PCCAML). Earlier studies used the counting results of the returned signal detected by a Geiger mode avalanche photodiode detector (Gm-APD) to mix with the reference signal, called the postmixing method. We use an alternative method known as the premixing method, in which the reference signal is used to directly modulate the sampling gate width of the Gm-APD, and the mixing of the returned signal and the reference signal is completed before the Gm-APD. This premixing method is more flexible and may perform better than the postmixing method in terms of signal-to-noise ratio by cutting down a separated mixer commonly used in the postmixing lidar system. Furthermore, this premixing method lowers the demand for the sampling frequency of the Gm-APD. It allows the use of a much wider modulation bandwidth to improve the range accuracy and resolution. To the best of our knowledge, this is the first report to use the premixing method in the PCCAML system, which will benefit future lidar applications. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1006 | |||
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| Author | Korneev, A. A.; Divochiy, A. V.; Vakhtomin, Yu. B.; Korneeva, Yu. P.; Larionov, P. A.; Manova, N. N.; Florya, I. N.; Trifonov, A. V.; Voronov, B. M.; Smirnov, K. V.; Semenov, A. V.; Chulkova, G. M.; Goltsman, G. N. | ||||
| Title | IR single-photon receiver based on ultrathin NbN superconducting film | Type | Journal Article | ||
| Year |
2013 | Publication | Rus. J. Radio Electron. | Abbreviated Journal | Rus. J. Radio Electron. |
| Volume | Issue | 5 | Pages | ||
| Keywords | SSPD, SNSPD | ||||
| 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. | ||||
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| Language | Russian | Summary Language | Original Title | ||
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| Notes | 8 pages | Approved | no | ||
| Call Number | RPLAB @ sasha @ korneevir | Serial | 1043 | ||
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| Author | McCarthy, Aongus; Krichel, Nils J.; Gemmell, Nathan R.; Ren, Ximing; Tanner, Michael G.; Dorenbos, Sander N.; Zwiller, Val; Hadfield, Robert H.; Buller, Gerald S. | ||||
| Title | Kilometer-range, high resolution depth imaging via 1560 nm wavelength single-photon detection | Type | Journal Article | ||
| Year |
2013 | Publication | Opt. Express | Abbreviated Journal | Opt. Express |
| Volume | 21 | Issue | 7 | Pages | 8904-8915 |
| Keywords | SSPD, SNSPD, lidar, SSPD applications, SNSPD applications | ||||
| Abstract | This paper highlights a significant advance in time-of-flight depth imaging: by using a scanning transceiver which incorporated a free-running, low noise superconducting nanowire single-photon detector, we were able to obtain centimeter resolution depth images of low-signature objects in daylight at stand-off distances of the order of one kilometer at the relatively eye-safe wavelength of 1560 nm. The detector used had an efficiency of 18% at 1 kHz dark count rate, and the overall system jitter was ~100 ps. The depth images were acquired by illuminating the scene with an optical output power level of less than 250 µW average, and using per-pixel dwell times in the millisecond regime. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1053 | |||
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| Author | Marsili, F.; Verma, V. B.; Stern, J. A.; Harrington, S.; Lita, A. E.; Gerrits, T.; Vayshenker, I.; Baek, B.; Shaw, M. D.; Mirin, R. P.; Nam, S. W. | ||||
| Title | Detecting single infrared photons with 93% system efficiency | Type | Journal Article | ||
| Year |
2013 | Publication | Nat. Photon. | Abbreviated Journal | |
| Volume | 7 | Issue | 3 | Pages | 210-214 |
| Keywords | SSPD quantum efficiency | ||||
| Abstract | Single-photon detectors1 at near-infrared wavelengths with high system detection efficiency (>90%), low dark count rate (<1 c.p.s.), low timing jitter (<100 ps) and short reset time (<100 ns) would enable landmark experiments in a variety of fields2, 3, 4, 5, 6. Although some of the existing approaches to single-photon detection fulfil one or two of the above specifications1, to date, no detector has met all of the specifications simultaneously. Here, we report on a fibre-coupled single-photon detection system that uses superconducting nanowire single-photon detectors7 and closely approaches the ideal performance of single-photon detectors. Our detector system has a system detection efficiency (including optical coupling losses) greater than 90% in the wavelength range λ = 1,520–1,610 nm, with a device dark count rate (measured with the device shielded from any background radiation) of ~1 c.p.s., timing jitter of ~150 ps full-width at half-maximum (FWHM) and reset time of 40 ns. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1056 | |||
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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. | ||||
| Title | Temperature dependence of superconducting hot electron bolometers | Type | Conference Article | ||
| Year |
2013 | Publication | Not published results: 24th international symposium on space terahertz technology | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | HEB | ||||
| Abstract | |||||
| Address | Groningen,The Netherlands | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1067 | |||
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| Author | Coumou, P. C. J. J.; Driessen, E. F. C.; Bueno, J.; Chapelier, C.; Klapwijk, T. M. | ||||
| Title | Electrodynamic response and local tunneling spectroscopy of strongly disordered superconducting TiN films | Type | Journal Article | ||
| Year |
2013 | Publication | Phys. Rev. B | Abbreviated Journal | |
| Volume | 88 | Issue | 18 | Pages | 180505 (1 to 5) |
| Keywords | strongly disordered superconducting TiN films, microwave resonators | ||||
| Abstract | We have studied the electrodynamic response of strongly disordered superconducting TiN films using microwave resonators, where the disordered superconductor is the resonating element in a high-quality superconducting environment of NbTiN. We describe the response assuming an effective pair-breaking mechanism modifying the density of states and compare this to local tunneling spectra obtained using scanning tunneling spectroscopy. For the least disordered film (kFl=8.7, Rs=13Ω), we find good agreement, whereas for the most disordered film (kFl=0.82, Rs=4.3kΩ), there is a strong discrepancy, which signals the breakdown of a model based on uniform properties. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1069 | |||
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| Author | Cavalié, T.; Feuchtgruber, H.; Lellouch, E.; de Val-Borro, M.; Jarchow, C.; Moreno, R.; Hartogh, P.; Orton, G.; Greathouse, T. K.; Billebaud, F.; Dobrijevic, M.; Lara, L. M.; González, A.; Sagawa, H. | ||||
| Title | Spatial distribution of water in the stratosphere of Jupiter from Herschel HIFI and PACS observations | Type | Journal Article | ||
| Year |
2013 | Publication | Astron. Astrophys. | Abbreviated Journal | |
| Volume | 553 | Issue | Pages | A21 (1 to 16) | |
| Keywords | HEB mixer applications, HIFI, Herschel | ||||
| Abstract | Context. In the past 15 years, several studies suggested that water in the stratosphere of Jupiter originated from the Shoemaker-Levy 9 (SL9) comet impacts in July 1994, but a direct proof was missing. Only a very sensitive instrument observing with high spectral/spatial resolution can help to solve this problem. This is the case of the Herschel Space Observatory, which is the first telescope capable of mapping water in Jupiter's stratosphere. Aims. We observed the spatial distribution of the water emission in Jupiter's stratosphere with the Heterodyne Instrument for the Far Infrared (HIFI) and the Photodetector Array Camera and Spectrometer (PACS) onboard Herschel to constrain its origin. In parallel, we monitored Jupiter's stratospheric temperature with the NASA Infrared Telescope Facility (IRTF) to separate temperature from water variability. Methods. We obtained a 25-point map of the 1669.9 GHz water line with HIFI in July 2010 and several maps with PACS in October 2009 and December 2010. The 2010 PACS map is a 400-point raster of the water 66.4 μm emission. Additionally, we mapped the methane ν4 band emission to constrain the stratospheric temperature in Jupiter in the same periods with the IRTF. Results. Water is found to be restricted to pressures lower than 2 mbar. Its column density decreases by a factor of 2–3 between southern and northern latitudes, consistently between the HIFI and the PACS 66.4 μm maps. We infer that an emission maximum seen around 15 °S is caused by a warm stratospheric belt detected in the IRTF data. Conclusions. Latitudinal temperature variability cannot explain the global north-south asymmetry in the water maps. From the latitudinal and vertical distributions of water in Jupiter's stratosphere, we rule out interplanetary dust particles as its main source. Furthermore, we demonstrate that Jupiter's stratospheric water was delivered by the SL9 comet and that more than 95% of the observed water comes from the comet according to our models. |
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| Notes | Approved | no | |||
| Call Number | Serial | 1085 | |||
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| Author | Pineda, J. L.; Langer, W. D.; Velusamy, T.; Goldsmith, P. F. | ||||
| Title | A Herschel [C ii] Galactic plane survey. I. The global distribution of ISM gas components | Type | Journal Article | ||
| Year |
2013 | Publication | Astron. Astrophys. | Abbreviated Journal | |
| Volume | 554 | Issue | Pages | A103 | |
| Keywords | HEB mixer applications, HIFI, Herschel, ISM: general / stars: formation / evolution / ISM: clouds / ISM: structure / submillimeter: ISM | ||||
| Abstract | Context. The [C ii] 158 μm line is an important tool for understanding the life cycle of interstellar matter. Ionized carbon is present in a variety of phases of the interstellar medium (ISM), including the diffuse ionized medium, warm and cold atomic clouds, clouds in transition from atomic to molecular, and dense and warm photon dominated regions. Aims. Velocity-resolved observations of [C ii] are the most powerful technique available to disentangle the emission produced by these components. These observations can also be used to trace CO-dark H2 gas and determine the total mass of the ISM. Methods. The Galactic Observations of Terahertz C+ (GOT C+) project surveys the [C ii] 158 μm line over the entire Galactic disk with velocity-resolved observations using the Herschel/HIFI instrument. We present the first longitude-velocity maps of the [C ii] emission for Galactic latitudes b = 0°, ±0.5°, and ±1.0°. We combine these maps with those of H i, 12CO, and 13CO to separate the different phases of the ISM and study their properties and distribution in the Galactic plane. Results. [C ii] emission is mostly associated with spiral arms, mainly emerging from Galactocentric distances between 4 and 10 kpc. It traces the envelopes of evolved clouds as well as clouds that are in the transition between atomic and molecular. We estimate that most of the observed [C ii] emission is produced by dense photon dominated regions (~47%), with smaller contributions from CO-dark H2 gas (~28%), cold atomic gas (~21%), and ionized gas (~4%). Atomic gas inside the Solar radius is mostly in the form of cold neutral medium (CNM), while the warm neutral medium gas dominates the outer galaxy. The average fraction of CNM relative to total atomic gas is ~43%. We find that the warm and diffuse CO-dark H2 is distributed over a larger range of Galactocentric distances (4–11 kpc) than the cold and dense H2 gas traced by 12CO and 13CO (4–8 kpc). The fraction of CO-dark H2 to total H2 increases with Galactocentric distance, ranging from ~20% at 4 kpc to ~80% at 10 kpc. On average, CO-dark H2 accounts for ~30% of the molecular mass of the Milky Way. When the CO-dark H2 component is included, the radial distribution of the CO-to-H2 conversion factor is steeper than that when only molecular gas traced by CO is considered. Most of the observed [C ii] emission emerging from dense photon dominated regions is associated with modest far-ultraviolet fields in the range χ0 â‰<192> 1 – 30. |
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1100 | |||
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| Author | Fedorov, G.; Kardakova, A.; Gayduchenko, I.; Charayev, I.; Voronov, B.M.; Finkel, M.; Klapwijk, T.M.; Morozov, S.; Presniakov, M.; Bobrinetskiy, I.; Ibragimov, R.; Goltsman, G. | ||||
| Title | Photothermoelectric response in asymmetric carbon nanotube devices exposed to sub-terahertz radiation | Type | Journal Article | ||
| Year |
2013 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 103 | Issue | 18 | Pages | 181121 (1 to 5) |
| Keywords | carbon nanotubes, CNT, THz radiation, SiO2 substrate | ||||
| Abstract | We report on the voltage response of carbon nanotube devices to sub-terahertz (THz) radiation. The devices contain carbon nanotubes (CNTs), which are over their length partially suspended and partially Van der Waals bonded to a SiO2 substrate, causing a difference in thermal contact. We observe a DC voltage upon exposure to 140 GHz radiation. Based on the observed gate voltage and power dependence, at different temperatures, we argue that the observed signal is both thermal and photovoltaic. The room temperature responsivity in the microwave to THz range exceeds that of CNT based devices reported before. Authors thank Professor P. Barbara for providing the catalyst for CNT growth and Dr. N. Chumakov and V. Rylkov for stimulating discussions. The work was supported by the RFBR (Grant No. 12-02-01291-a) and by the Ministry of Education and Science of the Russian Federation (Contract No. 14.B25.31.0007). G.F. acknowledges support of the RFBR grant 12-02-01005-a. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1171 | |||
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| Author | Elezov, M. S.; Semenov, A. V.; An, P. P.; Tarkhov, M. A.; Goltsman, G. N.; Kardakova, A. I.; Kazakov, A. Y. | ||||
| Title | Investigating the detection regimes of a superconducting single-photon detector | Type | Journal Article | ||
| Year |
2013 | Publication | J. Opt. Technol. | Abbreviated Journal | J. Opt. Technol. |
| Volume | 80 | Issue | 7 | Pages | 435 |
| Keywords | SSPD, quantum efficiency | ||||
| Abstract | The detection regimes of a superconducting single-photon detector have been investigated. A technique is proposed for determining the regions in which “pure regimes” predominate. Based on experimental data, the dependences of the internal quantum efficiency on the bias current are determined in the one-, two-, and three-photon detection regimes. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1070-9762 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1172 | |||
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| Author | Zolotov, P.; Vakhtomin, Yu.; Divochiy, A.; Seleznev, V.; Morozov, P.; Smirnov, K. | ||||
| Title | High-efficiency single-photon detectors based on NbN films | Type | Miscellaneous | ||
| Year |
2013 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | SSPD, SNSPD | ||||
| Abstract | We present our resent results in development and testing of Superconducting Single-Photon Detectors (SSPD) with detection efficiencies greater than 85%. High values of obtained results are assigned to proposed design of the detector with integrated resonator structure, including two-layer optical cavity and anti-reflective coating (ARC). | ||||
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| Notes | Poster | Approved | no | ||
| Call Number | Serial | 1254 | |||
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| Author | Peltonen, J. T.; Astafiev, O. V.; Korneeva, Y. P.; Voronov, B. M.; Korneev, A. A.; Charaev, I. M.; Semenov, A. V.; Golt'sman, G. N.; Ioffe, L. B.; Klapwijk, T. M.; Tsai, J. S. | ||||
| Title | Coherent flux tunneling through NbN nanowires | Type | Journal Article | ||
| Year |
2013 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
| Volume | 88 | Issue | 22 | Pages | 220506 (1 to 5) |
| Keywords | NbN nanowires | ||||
| Abstract | We demonstrate evidence of coherent magnetic flux tunneling through superconducting nanowires patterned in a thin highly disordered NbN film. The phenomenon is revealed as a superposition of flux states in a fully metallic superconducting loop with the nanowire acting as an effective tunnel barrier for the magnetic flux, and reproducibly observed in different wires. The flux superposition achieved in the fully metallic NbN rings proves the universality of the phenomenon previously reported for InOx. We perform microwave spectroscopy and study the tunneling amplitude as a function of the wire width, compare the experimental results with theories, and estimate the parameters for existing theoretical models. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1369 | |||
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| Author | Zhang, W.; Miao, W.; Li, S. L.; Zhou, K. M.; Shi, S. C.; Gao, J. R.; Goltsman, G. N. | ||||
| Title | Measurement of the spectral response of spiral-antenna coupled superconducting hot electron bolometers | Type | Journal Article | ||
| Year |
2013 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 23 | Issue | 3 | Pages | 2300804-2300804 |
| Keywords | NbN HEB detector | ||||
| Abstract | Measured spectral response of spiral-antenna coupled superconducting hot electron bolometers (HEBs) often drops dramatically at frequencies that are still within the frequency range of interest (e.g., ~ 5 THz). This is inconsistent with the implied low receiver noise temperatures from the same measurements. To understand this discrepancy, we exhaustively test and calibrate the thermal sources used in Fourier transform spectrometer measurements. We first investigate the absolute emission spectrum of high-pressure Hg arc lamp, then measure the spectral response of two spiral-antenna coupled NbN HEBs with a Martin-Puplett interferometer as spectrometer and 77 K blackbody as broadband signal source. The measured absolute emission spectrum of Hg arc lamp is proportional to frequency, corresponding to an equivalent blackbody temperature of 4000 K at 1 THz, 1500 K at 3 THz, and 800 K at 5 THz, respectively. Measured spectral response of spiral-antenna coupled NbN HEBs, corrected for air absorption, is nearly flat in the frequency range of 0.5-4 THz, consistent with simulated coupling efficiency between HEB and spiral-antenna. These results explain the discrepancy, and prove that spiral-antenna coupled superconducting NbN HEBs work well in a wide frequency range. In addition, this calibration method and these results are broadly applicable to other quasi-optical THz receivers. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1051-8223 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1371 | |||
| Permanent link to this record | |||||
| Author | Shurakov, A.; Tong, C.-Y. E.; Blundell, R.; Kaurova, N.; Voronov, B.; Gol'tsman, G. | ||||
| Title | Microwave stabilization of a HEB mixer in a pulse-tube cryocooler | Type | Journal Article | ||
| Year |
2013 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 23 | Issue | 3 | Pages | 1501504-1501504 |
| Keywords | NbN HEB mixers | ||||
| Abstract | We report the results of our study of the stability of an 800 GHz hot electron bolometer (HEB) mixer cooled with a pulse-tube cryocooler. Pulse-tube cryocoolers introduce temperature fluctuations as well as mechanical vibrations at a frequency of ~1 Hz, both of which can cause receiver gain fluctuations at that frequency. In our system, the motor of the cryocooler was separated from the cryostat to minimize mechanical vibrations, leaving thermal effects as the dominant source of the receiver gain fluctuations. We measured root mean square temperature variations of the 4 K stage of ~7 mK. The HEB mixer was pumped by a solid state local oscillator at 810 GHz. The root mean square current fluctuations at the low noise operating point (1.50 mV, 56.5 μA) were ~0.12 μA, and were predominantly due to thermal fluctuations. To stabilize the bias current, microwave radiation was injected to the HEB mixer. The injected power level was set by a proportional-integral-derivative controller, which completely compensates for the bias current oscillations induced by the pulse-tube cryocooler. Significant improvement in the Allan variance of the receiver output power was obtained, and an Allan time of 5 s was measured. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1051-8223 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1372 | |||
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| Author | Lusche, R.; Semenov, A.; Il'in, K.; Korneeva, Y.; Trifonov, A.; Korneev, A.; Hubers, H.; Siegel, M.; Gol'tsman, G. | ||||
| Title | Effect of the wire width and magnetic field on the intrinsic detection efficiency of superconducting nanowire single-photon detectors | Type | Journal Article | ||
| Year |
2013 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 23 | Issue | 3 | Pages | 2200205-2200205 |
| Keywords | SSPD, SNSPD | ||||
| Abstract | We present thorough measurements of the intrinsic detection efficiency in the wavelength range from 350 to 2500 nm for meander-type TaN and NbN superconducting nanowire single-photon detectors with different widths of the nanowire. The width varied from 70 nm to 130 nm. The open-beam configuration allowed us to accurately normalize measured spectra and to extract the intrinsic detection efficiency. For detectors from both materials the intrinsic detection efficiency at short wavelengths amounts at 100% and gradually decreases at wavelengths larger than the specific cut-off wavelengths, which decreases with the width of the nanowire. Furthermore, we show that applying weak magnetic fields perpendicular to the meander plane decreases the smallest detectable photon flux. | ||||
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| ISSN | 1051-8223 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1376 | |||
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