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Author Il’in, K. S.; Milostnaya, I. I.; Verevkin, A. A.; Gol’tsman, G. N.; Gershenzon, E. M.; Sobolewski, R.
Title Ultimate quantum efficiency of a superconducting hot-electron photodetector Type Journal Article
Year 1998 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 73 Issue 26 Pages 3938-3940
Keywords NbN SSPD, SNSPD
Abstract The quantum efficiency and current and voltage responsivities of fast hot-electron photodetectors, fabricated from superconducting NbN thin films and biased in the resistive state, have been shown to reach values of 340, 220 A/W, and 4×104 V/W,

respectively, for infrared radiation with a wavelength of 0.79 μm. The characteristics of the photodetectors are presented within the general model, based on relaxation processes in the nonequilibrium electron heating of a superconducting thin film. The observed, very high efficiency and sensitivity of the superconductor absorbing the photon are explained by the high multiplication rate of quasiparticles during the avalanche breaking of Cooper pairs.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951 ISBN Medium
Area Expedition Conference (up)
Notes Approved no
Call Number Serial 1579
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Author Ozhegov, R. V.; Gorshkov, K. N.; Smirnov, K. V.; Gol’tsman, G. N.; Filippenko, L. V.; Koshelets, V. P.
Title Terahertz imaging system based on superconducting integrated receiver Type Conference Article
Year 2010 Publication Proc. 2-nd Int. Conf. Terahertz and Microwave radiation: Generation, Detection and Applications Abbreviated Journal Proc. 2-nd Int. Conf. Terahertz and Microwave radiation: Generation, Detection and Applications
Volume Issue Pages 20-22
Keywords SIS mixer, SIR
Abstract The development of terahertz imaging instruments for security systems is on the cutting edge of terahertz technology. We are developing a THz imaging system based on a superconducting integrated receiver (SIR). An SIR is a new type of heterodyne receiver based on an SIS mixer integrated with a flux-flow oscillator (FFO) and a harmonic mixer which is used for phase-locking the FFO. Developing an array of SIRs would allow obtaining amplitude and phase characteristics of incident radiation in the plane of the receiver. Employing an SIR in an imaging system means building an entirely new instrument with many advantages compare to traditional systems: i) high temperature resolution, comparable to the best results for incoherent receivers; ii) high spectral resolution allowing spectral analysis of various substances; iii) the local oscillator frequency can be varied to obtain images at different frequencies, effectively providing “color” images; iv) since a heterodyne receiver preserves the phase of the radiation, it is possible to construct 3D images. The paper presents a prototype THz imaging system using an 1 pixel SIR. We have studied the dependence of the noise equivalent temperature difference (NETD) on the integration time and also possible ways of achieving best possible sensitivity. An NETD of 13 mK was obtained with an integration time of 1 sec a detection bandwidth of 4 GHz at a local oscillator frequency of 520 GHz. An important advantage of an FFO is its wide operation range: 300-700 GHz.
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Notes Approved no
Call Number ozhegov2010terahertz Serial 1397
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Author Ozhegov, R. V.; Okunev, O. V.; Gol’tsman, G. N.; Filippenko, L. V.; Koshelets, V. P.
Title Noise equivalent temperature difference of a superconducting integrated terahertz receiver Type Journal Article
Year 2009 Publication J. Commun. Technol. Electron. Abbreviated Journal J. Commun. Technol. Electron.
Volume 54 Issue 6 Pages 716-720
Keywords SIS mixer SIR NETD, FFO, harmonic mixer
Abstract The dependence of the noise equivalent temperature difference (NETD) of a superconducting integrated receiver (SIR) on the receiver noise temperature and the inputsignal level has been investigated. An unprecedented NETD of 13±2 mK has been measured at a SIR noise temperature of 200 K, intermediate-frequency bandwidth of 4 GHz, and time constant of 1 s. With a decrease in the input signal, an improvement in the NETD is observed. This effect is explained by a reduction in the influence of the instabilities of the receiver power supply and the amplification circuit that occur when the input signal is decreased.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1064-2269 ISBN Medium
Area Expedition Conference (up)
Notes Approved no
Call Number Serial 1400
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Author Beck, M.; Klammer, M.; Lang, S.; Leiderer, P.; Kabanov, V. V.; Gol’tsman, G. N.; Demsar, J.
Title Energy-gap dynamics of superconducting NbN thin films studied by time-resolved terahertz spectroscopy Type Miscellaneous
Year 2011 Publication arXiv Abbreviated Journal
Volume Issue Pages
Keywords NbN thin film, energy gap dynamics
Abstract Using time-domain Terahertz spectroscopy we performed direct studies of the photoinduced suppression and recovery of the superconducting gap in a conventional BCS superconductor NbN. Both processes are found to be strongly temperature and excitation density dependent. The analysis of the data with the established phenomenological Rothwarf-Taylor model enabled us to determine the bare quasiparticle recombination rate, the Cooper pair-breaking rate and the electron-phonon coupling constant, \lambda = 1.1 +/- 0.1, which is in excellent agreement with theoretical estimates.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference (up)
Notes Duplicated as 641 Approved no
Call Number Serial 1388
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Author Tret’yakov, I. V.; Ryabchun, S. A.; Kaurova, N. S.; Larionov, P. A.; Lobastova, A. A.; Voronov, B. M.; Finkel, M. I.; Gol’tsman, G. N.
Title Optimum absorbed heterodyne power for superconducting NbN hot-electron bolometer mixer Type Journal Article
Year 2010 Publication Tech. Phys. Lett. Abbreviated Journal Tech. Phys. Lett.
Volume 36 Issue 12 Pages 1103-1105
Keywords NbN HEB mixer
Abstract Absorbed heterodyne power has been measured in a low-noise broadband hot-electron bolometer (HEB) mixer for the terahertz range, operating on the effect of electron heating in the resistive state of an ultrathin superconducting NbN film. It is established that the optimum absorbed heterodyne power for the HEB mixer operating at 2.5 THz is about 100 nW.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-7850 ISBN Medium
Area Expedition Conference (up)
Notes Approved no
Call Number Serial 1389
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Author Gershenzon, E. M.; Gol’tsman, G. N.; Gousev, Y. P.; Elant’ev, A. I.; Semenov, A. D.
Title Electromagnetic radiation mixer based on electron heating in resistive state of superconductive Nb and YBaCuO films Type Journal Article
Year 1991 Publication IEEE Trans. Magn. Abbreviated Journal IEEE Trans. Magn.
Volume 27 Issue 2 Pages 1317-1320
Keywords YBCO, HTS, Nb HEB mixers
Abstract A theory of an electron-heating mixer which makes it possible to calculate all the characteristics of the device is developed. It is shown that positive conversion gain is possible for such a mixer in the millimeter to near-infrared wavelength range. The dynamic range and the optimum heterodyne power can be selected from a very wide interval by varying the mixing element volume. Measurements made for Nb within the frequency range of 120-750 GHz confirm the theory. The conversion loss obtained at T=1.6 K and normalized to the element reaches 0.3 dB in the intermediate frequency band of 40 MHz; the possible noise temperature is 50 K. The estimation of noise temperature and output band for YBaCuO at T=77 yields 200 K and more than 10 GHz, respectively.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1941-0069 ISBN Medium
Area Expedition Conference (up)
Notes Approved no
Call Number Serial 1681
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Author Beck, M.; Klammer, M.; Rousseau, I.; Gol’tsman, G. N.; Diamant, I.; Dagan, Y.; Demsar, J.
Title Probing superconducting gap dynamics with THz pulses Type Conference Article
Year 2015 Publication CLEO Abbreviated Journal CLEO
Volume Issue Pages SM3H.3 (1 to 2)
Keywords superconducting gap; electric fields; femtosecond pulses; near infrared radiation; picosecond pulses; superconductors; thin films
Abstract We studied superconducting gap dynamics in a BCS superconductor NbN and electron doped cuprate superconductor PCCO following excitation with near-infrared (NIR) and narrow band THz pulses. Systematic studies on PCCO imply very selective electron-phonon coupling.
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Corporate Author Thesis
Publisher Optical Society of America Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference (up)
Notes Approved no
Call Number Serial 1345
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Author Tuchak, A. N.; Gol’tsman, G. N.; Kitaeva, G. K.; Penin, A. N.; Seliverstov, S. V.; Finkel, M. I.; Shepelev, A. V.; Yakunin, P. V.
Title Generation of nanosecond terahertz pulses by the optical rectification method Type Journal Article
Year 2012 Publication JETP Lett. Abbreviated Journal JETP Lett.
Volume 96 Issue 2 Pages 94-97
Keywords optical rectification, lithium niobate crystal
Abstract The possibility of the generation of quasi-cw terahertz radiation by the optical rectification method for broad-band Fourier unlimited nanosecond laser pulses has been experimentally demonstrated. The broadband radiation of a LiF dye-center laser is used as a pump source of a nonlinear optical oscillator. The energy efficiency of terahertz optical frequency conversion in a periodically polarized lithium niobate crystal is 4 × 10−9 at a pump power density of 7 MW/cm2.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-3640 ISBN Medium
Area Expedition Conference (up)
Notes Approved no
Call Number Serial 1377
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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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-7842 ISBN Medium
Area Expedition Conference (up)
Notes Approved no
Call Number Serial 1378
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Author Ozhegov, R. V.; Gorshkov, K. N.; Okunev, O. V.; Gol’tsman, G. N.
Title Superconducting hot-electron bolometer mixer as element of thermal imager matrix Type Journal Article
Year 2010 Publication Tech. Phys. Lett. Abbreviated Journal Tech. Phys. Lett.
Volume 36 Issue 11 Pages 1006-1008
Keywords HEB mixers
Abstract The possibility of using a matrix of sensitive elements on a 12-mm-diameter hyperhemispherical lens in a thermal imager operating in the terahertz range has been studied. Dimensions of a lens region acceptable for arrangement of the matrix, in which the receiver noise temperature varies within 16% of the mean value, are determined to be 3.3% of the lens diameter. Deviations of the main lobe of the directivity pattern are evaluated, which amount to ±1.25° relative to the direction toward the optimum position of a mixer. The fluctuation sensitivity of the receiver measured in experiment is 0.5 K at a frequency of 300 GHz.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-7850 ISBN Medium
Area Expedition Conference (up)
Notes Approved no
Call Number Serial 1390
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