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| Author | Galin, M. A.; Klushin, A. M.; Kurin, V. V.; Seliverstov, S. V.; Finkel, M. I.; Goltsman, G. N.; Müller, F.; Scheller, T.; Semenov, A. D. | ||||
| Title | Towards local oscillators based on arrays of niobium Josephson junctions | Type | Journal Article | ||
Year  |
2015 | Publication | Supercond. Sci. Technol. | Abbreviated Journal | Supercond. Sci. Technol. |
| Volume | 28 | Issue | 5 | Pages | 055002 (1 to 7) |
| Keywords | Josephson junction local oscillators, JJ LO | ||||
| Abstract | Various applications in the field of terahertz technology are in urgent need of compact, wide-tunable solid-state continuous wave radiation sources with a moderate power. However, satisfactory solutions for the THz frequency range are scarce yet. Here we report on coherent radiation from a large planar array of Josephson junctions (JJs) in the frequency range between 0.1 and 0.3 THz. The external resonator providing the synchronization of JJ array is identified as a straight fragment of a single-strip-line containing the junctions themselves. We demonstrate a prototype of the quasioptical heterodyne receiver with the JJ array as a local oscillator and a hot-electron bolometer mixer. | ||||
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| ISSN | 0953-2048 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1347 | |||
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| Author | Sidorova, Maria V.; Divochiy, Alexander V.; Vakhtomin, Yury B.; Smirnov, Konstantin V. | ||||
| Title | Ultrafast superconducting single-photon detector with a reduced active area coupled to a tapered lensed single-mode fiber | Type | Journal Article | ||
| Year |
2015 | Publication | J. Nanophoton. | Abbreviated Journal | |
| Volume | 9 | Issue | 1 | Pages | 093051 |
| Keywords | SSPD, SNSPD | ||||
| Abstract | This paper presents an ultrafast niobium nitride (NbN) superconducting single-photon detector (SSPD) with an active area of 3×3 μm2 that offers better timing performance metrics than the previous SSPD with an active area of 7×7 μm2. The improved SSPD demonstrates a record timing jitter (<25 ps), an ultrashort recovery time (<2 ns), an extremely low dark count rate, and a high detection efficiency in a wide spectral range from visible part to near infrared. The record parameters were obtained due to the development of a new technique providing effective optical coupling between a detector with a reduced active area and a standard single-mode telecommunication fiber. The advantages of the new approach are experimentally confirmed by taking electro-optical measurements. | ||||
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| ISSN | 1934-2608 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | 10.1117/1.JNP.9.093051 | Approved | no | ||
| Call Number | RPLAB @ sasha @ | Serial | 1052 | ||
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| Author | Sidorova, Maria V.; Divochiy, Alexander; Vakhtomin, Yury B.; Smirnov, Konstantin V. | ||||
| Title | Ultrafast superconducting single-photon detector with reduced-size active area coupled to a tapered lensed single-mode fiber | Type | Conference Article | ||
| Year |
2015 | Publication | Proc. SPIE | Abbreviated Journal | |
| Volume | 9504 | Issue | Pages | 950408 (1 to 9) | |
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| Publisher | Place of Publication | Editor | International Society for Optics and Photonics | ||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ sasha @ sidorova2015ultrafast | Serial | 1051 | ||
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| Author | Dube, I.; Jiménez, D.; Fedorov, G.; Boyd, A.; Gayduchenko, I.; Paranjape, M.; Barbara, P. | ||||
| Title | Understanding the electrical response and sensing mechanism of carbon-nanotube-based gas sensors | Type | Journal Article | ||
| Year |
2015 | Publication | Carbon | Abbreviated Journal | Carbon |
| Volume | 87 | Issue | Pages | 330-337 | |
| Keywords | carbon nanotubes, CNT detectors, field effect transistors, FET | ||||
| Abstract | Gas sensors based on carbon nanotube field effect transistors (CNFETs) have outstanding sensitivity compared to existing technologies. However, the lack of understanding of the sensing mechanism has greatly hindered progress on calibration standards and customization of these nano-sensors. Calibration requires identifying fundamental transistor parameters and establishing how they vary in the presence of a gas. This work focuses on modeling the electrical response of CNTFETs in the presence of oxidizing (NO2) and reducing (NH3) gases and determining how the transistor characteristics are affected by gas-induced changes of contact properties, such as the Schottky barrier height and width, and by the doping level of the nanotube. From the theoretical fits of the experimental transfer characteristics at different concentrations of NO2 and NH3, we find that the CNTFET response can be modeled by introducing changes in the Schottky barrier height. These changes are directly related to the changes in the metal work function of the electrodes that we determine experimentally, independently, with a Kelvin probe. Our analysis yields a direct correlation between the ON – current and the changes in the electrode metal work function. Doping due to molecules adsorbed at the carbon-nanotube/metal interface also affects the transfer characteristics. | ||||
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| ISSN | 0008-6223 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1778 | |||
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| Author | Vodolazov, D. Y.; Korneeva, Y. P.; Semenov, A. V.; Korneev, A. A.; Goltsman, G. N. | ||||
| Title | Vortex-assisted mechanism of photon counting in a superconducting nanowire single-photon detector revealed by external magnetic field | Type | Journal Article | ||
| Year |
2015 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
| Volume | 92 | Issue | 10 | Pages | 104503 (1 to 9) |
| Keywords | SSPD, SNSPD | ||||
| Abstract | We use an external magnetic field to probe the detection mechanism of a superconducting nanowire single-photon detector. We argue that the hot belt model (which assumes partial suppression of the superconducting order parameter Δ across the whole width of the superconducting nanowire after absorption of the photon) does not explain observed weak-field dependence of the photon count rate (PCR) for photons with λ=450nm and noticeable decrease of PCR (with increasing the magnetic field) in a range of the currents for photons with wavelengths λ=450–1200nm. Found experimental results for all studied wavelengths can be explained by the vortex hot spot model (which assumes partial suppression of Δ in the area with size smaller than the width of the nanowire) if one takes into account nucleation and entrance of the vortices to the photon induced hot spot and their pinning by the hot spot with relatively large size and strongly suppressed Δ. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1343 | |||
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| Author | Kahl, O.; Ferrari, S.; Kovalyuk, V.; Goltsman, G. N.; Korneev, A.; Pernice, W. H. P. | ||||
| Title | Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths | Type | Journal Article | ||
| Year |
2015 | Publication | Sci. Rep. | Abbreviated Journal | Sci. Rep. |
| Volume | 5 | Issue | Pages | 10941 (1 to 11) | |
| Keywords | optical waveguides; waveguide integrated SSPD; waveguide SSPD; nanophotonics | ||||
| Abstract | Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present efficiencies close to unity at 1550nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noiseequivalent powers in the 10–19W/Hz–1/2 range and the timing jitter is as low as 35ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms. | ||||
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| Notes | PMID:26061283; PMCID:PMC4462017 | Approved | no | ||
| Call Number | RPLAB @ kovalyuk @ | Serial | 946 | ||
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| Author | Ferrari, S.; Kahl, O.; Kovalyuk, V.; Goltsman, G. N.; Korneev, A.; Pernice, W. H. P. | ||||
| Title | Waveguide-integrated single- and multi-photon detection at telecom wavelengths using superconducting nanowires | Type | Journal Article | ||
| Year |
2015 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 106 | Issue | 15 | Pages | 151101 (1 to 5) |
| Keywords | SSPD, SNSPD | ||||
| Abstract | We investigate single- and multi-photon detection regimes of superconducting nanowire detectors embedded in silicon nitride nanophotonic circuits. At near-infrared wavelengths, simultaneous detection of up to three photons is observed for 120 nm wide nanowires biased far from the critical current, while narrow nanowires below 100 nm provide efficient single photon detection. A theoretical model is proposed to determine the different detection regimes and to calculate the corresponding internal quantum efficiency. The predicted saturation of the internal quantum efficiency in the single photon regime agrees well with plateau behavior observed at high bias currents. W. H. P. Pernice acknowledges support by the DFG Grant Nos. PE 1832/1-1 and PE 1832/1-2 and the Helmholtz society through Grant No. HIRG-0005. The Ph.D. education of O. Kahl is embedded in the Karlsruhe School of Optics and Photonics (KSOP). G. N. Goltsman acknowledges support by Russian Federation President Grant HШ-1918.2014.2 and Ministry of Education and Science of the Russian Federation Contract No.: RFMEFI58614X0007. A. Korneev acknowledges support by Statement Task No. 3.1846.2014/k. V. Kovalyuk acknowledges support by Statement Task No. 2327. We also acknowledge support by the Deutsche Forschungsgemeinschaft (DFG) and the State of Baden-Württemberg through the DFG-Center for Functional Nanostructures (CFN) within subproject A6.4. We thank S. Kühn and S. Diewald for the help with device fabrication as well as B. Voronov and A. Shishkin for help with NbN thin film deposition and A. Semenov for helpful discussion about the detection mechanism of nanowire SSPD's. The authors declare no competing financial interests. |
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| ISSN | 0003-6951 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1211 | |||
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| Author | Лесс, Ю. А.; Кирсанов, Ю. А. | ||||
| Title | Былое и думы. Посвящение эпохе Н. Н. Малова, Е. М. Гершензона, В. С. Эткина | Type | Miscellaneous | ||
| Year |
2015 | Publication | ПРФЛ | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | физфак МПГУ, физфак МГПИ, ПРФЛ | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1132 | |||
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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. | ||||
| Title | Спонтанные и фотоиндуцированные резистивные состояния в узких сверхпроводящих NbN полосках | Type | Book Whole | ||
| Year |
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 | ||
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| 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 | Tong, C. Edward; Trifonov, Andrey; Blundell, Raymond; Shurakov, Alexander; Gol’tsman, Gregory | ||||
| Title | A digital terahertz power meter based on an NbN thin film | Type | Abstract | ||
| Year |
2014 | Publication | Proc. 25th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 25th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 170 | ||
| Keywords | waveguide NbN HEB mixers | ||||
| Abstract | We have further studied the effect of subjecting a superconducting Hot Electron Bolometer (HEB) element made from an NbN thin film to microwave radiation. Since the photon energy is weak, the microwave radiation does not simply heat the film, but generates a bi-static state, switching between the superconducting and normal states, upon the application of a small voltage bias. Indeed, a relaxation oscillation of a few MHz has previously been reported in this regime [1]. Switching between the superconducting and normal states modulates the reflected microwave pump power from the device. A simple homodyne setup readily recovers the spontaneous switching waveform in the time domain. The switching frequency is a function of both the bias voltage (DC heating) and the applied microwave power. In this work, we use a 0.8 THz HEB waveguide mixer for the purpose of demonstration. The applied microwave pump, coupled through a directional coupler, is at 1 GHz. Since the pump power is of the order of a few μW, a room temperature amplifier is sufficient to amplify the reflected pump power from the HEB mixer, which beats with the microwave source in a homodyne set-up. After further amplification, the switching waveform is passed onto a frequency counter. The typical frequency of the switching pulses is 3-5 MHz. It is found that the digital frequency count increases with higher microwave pump power. When the HEB mixer is subjected to additional optical power at 0.8 THz, the frequency count also increases. When we vary the incident optical power by using a wire grid attenuator, a linear relationship is observed between the frequency count and the applied optical power, over at least an order of magnitude of power. This phenomenon can be exploited to develop a digital power meter, using a very simple electronics setup. Further experiments are under way to determine the range of linearity and the accuracy of calibration transfer from the microwave to the THz regime. References 1. Y. Zhuang, and S. Yngvesson, “Detection and interpretation of bistatic effects in NbN HEB devices,” Proc. 13 th Int. Symp. Space THz Tech., 2002, pp. 463–472. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1366 | |||
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