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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 (up) 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 Iomdina, E. N.; Goltsman, G. N.; Seliverstov, S. V.; Sianosyan, A. A.; Teplyakova, K. O.; Rusova, A. A.
Title Study of transmittance and reflectance spectra of the cornea and the sclera in the THz frequency range Type Journal Article
Year 2016 Publication J. Biomed. Opt. Abbreviated Journal J. Biomed. Opt.
Volume (up) 21 Issue 9 Pages 97002 (1 to 5)
Keywords BWO, IMPATT diode, Schottky diode, medicine, animals, cornea, physiology, humans, rabbits, sclera diagnostic imaging, physiology
Abstract An adequate water balance (hydration extent) is one of the basic factors of normal eye function, including its external shells: the cornea and the sclera. Adequate control of corneal and scleral hydration is very important for early diagnosis of a variety of eye diseases, stating indications for and contraindications against keratorefractive surgeries and the choice of contact lens correction solutions. THz systems of creating images in reflected beams are likely to become ideal instruments of noninvasive control of corneal and scleral hydration degrees. This paper reports on the results of a study involving transmittance and reflectance spectra for the cornea and the sclera of rabbit and human eyes, as well as those of the rabbit eye, in the frequency range of 0.13 to 0.32 THz. The dependence of the reflectance coefficient of these tissues on water mass percentage content was determined. The experiments were performed on three corneas, three rabbit scleras, two rabbit eyes, and three human scleras. The preliminary results demonstrate that the proposed technique, based on the use of a continuous THz radiation, may be utilized to create a device for noninvasive control of corneal and scleral hydration, which has clear potential of broad practical application.
Address Moscow State Pedagogical University, Department of Physics, 29 Malaya Pirogovskaya Street, Moscow 119435, Russia
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Language English Summary Language Original Title
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Series Volume Series Issue Edition
ISSN 1083-3668 ISBN Medium
Area Expedition Conference
Notes PMID:27626901 Approved no
Call Number Serial 1335
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Author Voevodin, E. I.; Gershenzon, E. M.; Goltsman, G. N.; Ptitsina, N. G.; Chulkova, G. M.
Title Capture of free holes by charged acceptors in uniaxially deformed Ge Type Journal Article
Year 1988 Publication Fizika i Tekhnika Poluprovodnikov Abbreviated Journal Fizika i Tekhnika Poluprovodnikov
Volume (up) 22 Issue 3 Pages 540-543
Keywords Ge, free holes, capture
Abstract Цель настоящей работы — исследование кинетики примесной фотопрово­димости p-Ge при сильном одноосном сжатии в широком диапазоне изменения интенсивности примесного подсвета, создающего свободные дырки, и опреде­ление сечения каскадного захвата дырок на мелкие заряженные акцепторы в условиях преобладания электрон-фононного механизма потерь энергии.
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Language Russian Summary Language Original Title
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Notes Захват свободных дырок заряженными акцепторами в одноосно деформированном Ge Approved no
Call Number Serial 1698
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Author Gershenzon, E. M.; Orlov, L. A.; Ptitsina, N. G.
Title Absorption spectra in electron transitions between excited states of impurities in germanium Type Journal Article
Year 1975 Publication JETP Lett. Abbreviated Journal JETP Lett.
Volume (up) 22 Issue 4 Pages 95-97
Keywords Ge, impurities, excited states, absorption spectra
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Notes Approved no
Call Number Serial 1773
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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 (up) 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 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 1373
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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 (up) 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 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 (up) 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
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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 (up) 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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ISSN 1051-8223 ISBN Medium
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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 (up) 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
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Notes Approved no
Call Number Serial 1376
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Author Sclafani, M.; Marksteiner, M.; Keir, F. M. L.; Divochiy, A.; Korneev, A.; Semenov, A.; Gol'tsman, G.; Arndt, M.
Title Sensitivity of a superconducting nanowire detector for single ions at low energy Type Journal Article
Year 2012 Publication Nanotechnol. Abbreviated Journal Nanotechnol.
Volume (up) 23 Issue 6 Pages 065501 (1 to 5)
Keywords NbN SSPD, SNSPD, superconducting single ion detector, SSID, SNSID
Abstract We report on the characterization of a superconducting nanowire detector for ions at low kinetic energies. We measure the absolute single-particle detection efficiency eta and trace its increase with energy up to eta = 100%. We discuss the influence of noble gas adsorbates on the cryogenic surface and analyze their relevance for the detection of slow massive particles. We apply a recent model for the hot-spot formation to the incidence of atomic ions at energies between 0.2 and 1 keV. We suggest how the differences observed for photons and atoms or molecules can be related to the surface condition of the detector and we propose that the restoration of proper surface conditions may open a new avenue for SSPD-based optical spectroscopy on molecules and nanoparticles.
Address Vienna Center for Quantum Science and Technology, Faculty of Physics, University of Vienna, Vienna, Austria
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Language English Summary Language Original Title
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Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Medium
Area Expedition Conference
Notes PMID:22248823 Approved no
Call Number Serial 1380
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