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Author (up) Verevkin, A. A.; Zhang, J.; Slysz, W.; Sobolewski, R.; Lipatov, A. P.; Okunev, O.; Chulkova, G.; Korneev, A.; Gol’tsman, G. N.
Title Superconducting single-photon detectors for GHz-rate free-space quantum communications Type Conference Article
Year 2002 Publication Proc. SPIE Abbreviated Journal Proc. SPIE
Volume 4821 Issue Pages 447-454
Keywords NbN SSPD, SNSPD, single-photon detector, thin-film superconductivity, quantum cryptography, ultrafast communications
Abstract We report our studies on the performance of new NbN ultrathin-film superconducting single-photon detectors (SSPDs). Our SSPDs exhibit experimentally measured quantum efficiencies from   5% at wavelength λ = 1550 nm up to  10% at λ = 405 nm, with exponential, activation-energy-type spectral sensitivity dependence in the 0.4-μm – 3-μm wavelength range. Using a variable optical delay setup, we have shown that our NbN SSPDs can resolve optical photons with a counting rate up to 10 GHz, presently limited by the read-out electronics. The measured device jitter was below 35 ps under optimum biasing conditions. The extremely high photon counting rate, together with relatively high (especially for λ > 1 μm) quantum efficiency, low jitter, and very low dark counts, make NbN SSPDs very promising for free-space communications and quantum cryptography.
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Publisher SPIE Place of Publication Editor Ricklin, J.C.; Voelz, D.G.
Language Summary Language Original Title
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Area Expedition Conference Free-Space Laser Communication and Laser Imaging II
Notes Approved no
Call Number Serial 1523
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Author (up) Yngvesson, K. S.; Gerecht, E.; Musante, C. F.; Zhuang, Y.; Ji, M.; Goyette, T. M.; Dickinson, J. C.; Waldman, J.; Yagoubov, P. A.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
Title Low-noise HEB heterodyne receivers and focal plane arrays for the THz regime using NbN Type Conference Article
Year 1999 Publication Proc. SPIE Abbreviated Journal Proc. SPIE
Volume 3795 Issue Pages 357-368
Keywords NbN HEB mixers
Abstract We have developed prototype HEB receivers using thin film superconducting NbN devices deposited on silicon substrates. The devices are quasi-optically coupled through a silicon lens and a self-complementary log-specific toothed antenna. We measured DSB receiver noise temperatures of 500 K (13 X hf/2k) at 1.56 THz and 1,100 K (20 X hf/2k) at 2.24 THz. Noise temperatures are expected to fall further as devices and quasi-optical coupling methods are being optimized. The measured 3 dB IF conversion gain bandwidth for one device was 3 GHz, and it is estimated that the bandwidth over which the receiver noise temperature is within 3 dB of its minimum value is 6.5 GHz which is sufficient for a number of practical applications. We will discuss our latest results and give a detailed description of our prototype setup and experiments. We will also discuss our plans for developing focal plane arrays with tens of Hot Electron Bolometric mixer elements on a single silicon substrate which will make real time imaging systems in the THz region feasible.
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Corporate Author Thesis
Publisher SPIE Place of Publication Editor Hwu, R.J.; Wu, K.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference Terahertz and Gigahertz Photonics
Notes Approved no
Call Number Serial 1561
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Author (up) Yorke, Harold W.; Paine, Christopher G.; Bradford, Charles M.; Mark Dragovan; Nash, Al E.; Dooley, Jennifer A.; Lawrence, Charles R.
Title Thermal design trades for SAFIR architecture concepts Type Conference Article
Year 2004 Publication Proc. SPIE Abbreviated Journal
Volume 5487 Issue Pages 1617-1624
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ s @ sun_shield_SAFIR_SPIE_2004 Serial 340
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Author (up) Zhang, J.; Verevkin, A.; Slysz, W.; Chulkova, G.; Korneev, A.; Lipatov, A.; Okunev, O.; Gol’tsman, G. N.; Sobolewski, Roman
Title Time-resolved characterization of NbN superconducting single-photon optical detectors Type Conference Article
Year 2017 Publication Proc. SPIE Abbreviated Journal Proc. SPIE
Volume 10313 Issue Pages 103130F (1 to 3)
Keywords NbN SSPD, SNSPD
Abstract NbN superconducting single-photon detectors (SSPDs) are very promising devices for their picosecond response time, high intrinsic quantum efficiency, and high signal-to-noise ratio within the radiation wavelength from ultraviolet to near infrared (0.4 gm to 3 gm) [1-3]. The single photon counting property of NbN SSPDs have been investigated thoroughly and a model of hotspot formation has been introduced to explain the physics of the photon- counting mechanism [4-6]. At high incident flux density (many-photon pulses), there are, of course, a large number of hotspots simultaneously formed in the superconducting stripe. If these hotspots overlap with each other across the width w of the stripe, a resistive barrier is formed instantly and a voltage signal can be generated. We assume here that the stripe thickness d is less than the electron diffusion length, so the hotspot region can be considered uniform. On the other hand, when the photon flux is so low that on average only one hotspot is formed across w at a given time, the formation of the resistive barrier will be realized only when the supercurrent at sidewalks surpasses the critical current (jr) of the superconducting stripe [1]. In the latter situation, the formation of the resistive barrier is associated with the phase-slip center (PSC) development. The effect of PSCs on the suppression of superconductivity in nanowires has been discussed very recently [8, 9] and is the subject of great interest.
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Publisher SPIE Place of Publication Editor Armitage, J. C.
Language Summary Language Original Title
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Area Expedition Conference Opto-Canada: SPIE Regional Meeting on Optoelectronics, Photonics, and Imaging, 2002, Ottawa, Ontario, Canada
Notes Downloaded from http://www2.ece.rochester.edu/projects/ufqp/PDF/2002/213NbNTimeOPTO_b.pdf This artcle was published in 2017 with only first author indicated (Zhang, J.). There were 8 more authors! Approved no
Call Number Serial 1750
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Author (up) Zhang, W.; Li, N.; Jiang, L.; Ren, Y.; Yao, Q.-J.; Lin, Z.-H.; Shi, S.-C.; Voronov, B. M.; Gol’tsman, G. N.
Title Dependence of noise temperature of quasi-optical superconducting hot-electron bolometer mixers on bath temperature and optical-axis displacement Type Conference Article
Year 2008 Publication Proc. SPIE Abbreviated Journal Proc. SPIE
Volume 6840 Issue Pages 684007 (1 to 8)
Keywords NbN HEB mixers, noise temperature, LO power
Abstract It is known that the increase of bath temperature results in the decrease of critical current of superconducting hot-electron bolometer (HEB) mixers owing to the depression of superconductivity, thus leading to the degradation of the mixer’s sensitivity. Here we report our study on the effect of bath temperature on the heterodyne mixing performance of quasi-optical superconducting NbN HEB mixers incorporated with a two-arm log-spiral antenna. The correlation between the bath temperature, critical current, LO power requirement and noise temperature is investigated at 0.5 THz. Furthermore, the heterodyne mixing performance of quasi-optical superconducting NbN HEB mixers is examined while there is an optical-axis displacement between the center of the extended hemispherical silicon lens and the superconducting NbN HEB device, which is placed on the back of the lens. Detailed experimental results and analysis are presented.
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Corporate Author Thesis
Publisher Spie Place of Publication Editor Zhang, C.; Zhang, X.-C.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference Terahertz Photonics
Notes Approved no
Call Number Serial 1415
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