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	Author	Gershenzon, E. M.; Gol’tsman, G. N.; Sergeev, A.; Semenov, A. D.
	Title	Picosecond response of YBaCuO films to electromagnetic radiation			Type	Conference Article
	Year	1990	Publication	Proc. European Conf. High-Tc Thin Films and Single Crystals	Abbreviated Journal	Proc. European Conf. High-Tc Thin Films and Single Crystals
	Volume		Issue		Pages	457-462
	Keywords	YBCO HTS detectors
	Abstract	Radiation-induced change of the resistance was studied in the resistive state of YBaCuO films. Electron-phonon relaxation time T h was determmed from direct ep measurements and analysis of quasistationary electron heating. Temperature dependence of That TS 40 K was found to – ep be T h.. T'. The resul ts show that ep detectors with the response time of few picosecond at nitrogen temperature can be realized.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor	Gorzkowski, W.; Gutowski, M.; Reich, A.; Szymczak, H.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	European Conference , Ustroń, Poland , 30 Sept – 4 Oct 1989
	Notes				Approved	no
	Call Number				Serial	1695
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	Author	Antipov, S.; Trifonov, A.; Krause, S.; Meledin, D.; Desmaris, V.; Belitsky, V.; Gol’tsman, G.
	Title	Gain bandwidth of NbN HEB mixers on GaN buffer layer operating at 2 THz local oscillator frequency			Type	Conference Article
	Year	2017	Publication	Proc. 28^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 28^th Int. Symp. Space Terahertz Technol.
	Volume		Issue		Pages	147-148
	Keywords	NbN HEB mixers, GaN buffer-layer, IF bandwidth
	Abstract	In this paper, we present IF bandwidth measurement results of NbN HEB mixers, which are employing NbN thin films grown on a GaN buffer-layer. The HEB mixers were operated in the heterodyne regime at a bath temperature of approximately 4.5 K and with a local oscillator operating at a frequency of 2 THz. A quantum cascade laser served as the local oscillator and a reference synthesizer based on a BWO generator (130-160 GHz) and a semiconductor superlattice (SSL) frequency multiplier was used as a signal source. By changing the LO frequency it was possible to record the IF response or gain bandwidth of the HEB with a spectrum analyzer at the operation point, which yielded lowest noise temperature. The gain bandwidth that was recorded in the heterodyne regime at 2 THz amounts to approximately 5 GHz and coincides well with a measurement that has been performed at elevated bath temperatures and lower LO frequency of 140 GHz. These findings strongly support that by using a GaN buffer-layer the phonon escape time of NbN HEBs can be significantly lower as compared to e.g. Si substrate, thus, providing higher gain bandwidth.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1175
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	Author	Semenov, A. D.; Gol’tsman, G. N.; Gogidze, I. G.; Sergeev, A. V.; Gershenzon, E. M.; Lang, P. T.; Renk, K. F.
	Title	Subnanosecond photoresponse of a YBaCuO thin film to infrared and visible radiation by quasiparticle induced suppression of superconductivity			Type	Journal Article
	Year	1992	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	60	Issue	7	Pages	903-905
	Keywords	YBCO HTS detectors
	Abstract	We observed subnanosecond photoresponse of a structured superconducting YBa2Cu3O7−δ thin film to infrared and visible radiation. We measured the voltage response of a current biased film (thickness 700 Å) in a resistive state to radiation pulses. From our results we conclude a response time of about 90 ps and a responsivity of about 4×1010 Ω/J. We attribute the response to Cooper pair breaking and suppression of the superconducting energy gap induced by nonequilibrium quasiparticles.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1672
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	Author	Semenov, A. D.; Goghidze, I. G.; Gol’tsman, G. N.; Sergeev, A. V.; Gershenzon, E. M.
	Title	Evidence for the spectral dependence of nonequilibrium picosecond photoresponse of YBaCuO thin films			Type	Journal Article
	Year	1993	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	63	Issue	5	Pages	681-683
	Keywords	YBCO HTS detectors, nonequilibrium
	Abstract	The transient voltage photoresponse of current biased YBaCuO thin films to 20 ps laser pulses of 0.63 and 1.54 μm wavelengths is measured for temperatures around the superconducting transition region. The fast picosecond decay of the response is followed by a slow nanosecond relaxation which is associated with the bolometric effect. The magnitude of the fast component of the response varies in proportion to the square root of wavelength that plausibly reflects multiplication processes of photoexcited electrons via electron–electron scattering and interaction with high energy phonons.
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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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1655
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	Author	Lindgren, M.; Trifonov, V.; Zorin, M.; Danerud, M.; Winkler, D.; Karasik, B. S.; Gol’tsman, G. N.; Gershenzon, E.M.
	Title	Transient resistive photoresponse of YBa₂Cu₃O_7−δ films using low power 0.8 and 10.6 μm laser radiation			Type	Journal Article
	Year	1994	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	64	Issue	22	Pages	3036-3038
	Keywords	YBCO HTS HEB, nonequilibrium
	Abstract	Thin YBa2Cu3O7−δ laser deposited films were patterned into devices consisting of ten parallel 1 μm wide strips. Nonequilibrium picosecond and bolometric photoresponses were studied by the use of 17 ps full width at half‐maximum laser pulses and amplitude modulated radiation from an AlGaAs laser up to 10 GHz and from a CO2 laser up to 1 GHz. The time and frequency domain measurements were in agreement. The fast response can be explained by electron heating. The use of low optical power and a sensitive measurement system excluded any nonlinear transient processes and kinetic inductance changes in the superconducting state. At 1 GHz modulation frequency, the responsivity was ∼1.2 V/W both for 0.8 and 10.6 μm wavelengths. The sensitivity of a fast and spectrally broadband infrared detector is discussed.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1639
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	Author	Trifonov, V. A.; Karasik, B. S.; Zorin, M. A.; Gol’tsman, G. N.; Gershenzon, E. M.; Lindgren, M.; Danerud, M.; Winkler, D.
	Title	9.6 μm wavelength mixing in a patterned YBa₂Cu₃O_7‐δ thin film			Type	Journal Article
	Year	1996	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	68	Issue	10	Pages	1418-1420
	Keywords	YBCO HTS HEB mixers
	Abstract	Hot‐electron bolometric (HEB) mixing of 9.6 μm infrared radiation from two lasers in high‐quality YBa2Cu3O7−δ (YBCO) patterned thin film has been demonstrated. A heterodyne measurement showed an intermediate frequency (IF) bandwidth of 18 GHz, limited by our measurement system. An intrinsic limit of 100 GHz is predicted. Between 0.1 and 1 GHz intermediate frequency, temperature fluctuations with an equivalent output noise temperature Tfl up to ∼150 K, contributed to the mixer noise while Johnson noise dominated above 1 GHz. The overall conversion loss at 77 K at low intermediate frequencies was measured to be ∼25 dB, of which 13 dB was due to the coupling loss. The HEB mixer is very promising for use in heterodyne receivers within the whole infrared range.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1613
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	Author	Semenov, A. D.; Gousev, Y. P.; Nebosis, R. S.; Renk, K. F.; Yagoubov, P.; Voronov, B. M.; Gol’tsman, G. N.; Syomash, V. D.; Gershenzon, E. M.
	Title	Heterodyne detection of THz radiation with a superconducting hot‐electron bolometer mixer			Type	Journal Article
	Year	1996	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	69	Issue	2	Pages	260-262
	Keywords	NbN HEB mixers
	Abstract	We report on the use of a superconducting hot‐electron bolometer mixer for heterodyne detection of terahertz radiation. Radiation with a wavelength of 119 μm was coupled to the mixer, a NbN microbridge, by a hybrid quasioptical antenna consisting of an extended hyperhemispherical lens and a planar logarithmic spiral antenna. We found, at an intermediate frequency of 1.5 GHz, a system double side band noise temperature of ≊40 000 K and conversion losses of 25 dB. We also discuss the possibilities of further improvement of the mixer performance.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1610
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	Author	Kawamura, J.; Blundell, R.; Tong, C.-yu E.; Gol’tsman, G.; Gershenzon, E.; Voronov, B.; Cherednichenko, S.
	Title	Low noise NbN lattice-cooled superconducting hot-electron bolometric mixers at submillimeter wavelengths			Type	Journal Article
	Year	1997	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	70	Issue	12	Pages	1619-1621
	Keywords	NbN HEB mixers
	Abstract	Lattice-cooled superconducting hot-electron bolometric mixers are used in a submillimeter-wave waveguide heterodyne receiver. The mixer elements are niobium nitride film with 3.5 nm thickness and ∼10 μm2 area. The local oscillator power for optimal performance is estimated to be 0.5 μW, and the instantaneous bandwidth is 2.2 GHz. At an intermediate frequency centered at 1.4 GHz with 200 MHz bandwidth, the double sideband receiver noise temperature is 410 K at 430 GHz. The receiver has been used to detect molecular line emission in a laboratory gas cell.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1599
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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.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1579
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	Author	Gol’tsman, G. N.; Okunev, O.; Chulkova, G.; Lipatov, A.; Semenov, A.; Smirnov, K.; Voronov, B.; Dzardanov, A.; Williams, C.; Sobolewski, R.
	Title	Picosecond superconducting single-photon optical detector			Type	Journal Article
	Year	2001	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	79	Issue	6	Pages	705-707
	Keywords	NbN SSPD, SNSPD
	Abstract	We experimentally demonstrate a supercurrent-assisted, hotspot-formation mechanism for ultrafast detection and counting of visible and infrared photons. A photon-induced hotspot leads to a temporary formation of a resistive barrier across the superconducting sensor strip and results in an easily measurable voltage pulse. Subsequent hotspot healing in ∼30 ps time frame, restores the superconductivity (zero-voltage state), and the detector is ready to register another photon. Our device consists of an ultrathin, very narrow NbN strip, maintained at 4.2 K and current-biased close to the critical current. It exhibits an experimentally measured quantum efficiency of ∼20% for 0.81 μm wavelength photons and negligible dark counts.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1543
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	Author	Hübers, H.-W.; Semenov, A.; Holldack, K.; Schade, U.; Wüstefeld, G.; Gol’tsman, G.
	Title	Time domain analysis of coherent terahertz synchrotron radiation			Type	Journal Article
	Year	2005	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	87	Issue	18	Pages	184103 (1 to 3)
	Keywords	NbN HEB mixers, applications
	Abstract	The time structure of coherent terahertz synchrotron radiation at the electron storage ring of the Berliner Elektronensynchrotron und Speicherring Gesellschaft has been analyzed with a fast superconducting hot-electron bolometer. The emission from a single bunch of electrons was found to last ∼1500ps at frequencies around 0.4THz, which is much longer than the length of an electron bunch in the time domain (∼5ps). It is suggested that this is caused by multiple reflections at the walls of the beam line. The quadratic increase of the power with the number of electrons in the bunch as predicted for coherent synchrotron radiation and the transition from stable to bursting radiation were determined from a single storage ring fill pattern of bunches with different populations.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1457
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	Author	Kerman, A. J.; Dauler, E. A.; Keicher, W. E.; Yang, J. K. W.; Berggren, K. K.; Gol’tsman, G.; Voronov, B.
	Title	Kinetic-inductance-limited reset time of superconducting nanowire photon counters			Type	Journal Article
	Year	2006	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	88	Issue	11	Pages	111116 (1 to 3)
	Keywords	NbN SSPD, SNSPD
	Abstract	We investigate the recovery of superconducting NbN-nanowire photon counters after detection of an optical pulse at a wavelength of 1550nm, and present a model that quantitatively accounts for our observations. The reset time is found to be limited by the large kinetic inductance of these nanowires, which forces a tradeoff between counting rate and either detection efficiency or active area. Devices of usable size and high detection efficiency are found to have reset times orders of magnitude longer than their intrinsic photoresponse time. The authors acknowledge D. Oates and W. Oliver (MIT Lincoln Laboratory), S.W. Nam, A. Miller, and R. Hadfield (NIST) and R. Sobolewski, A. Pearlman, and A. Verevkin (University of Rochester) for helpful discussions and technical assistance. This work made use of MIT’s shared scanning-electron-beam-lithography facility in the Research Laboratory of Electronics. This work is sponsored by the United States Air Force under Air Force Contract No. FA8721-05-C-0002. Opinions, interpretations, recommendations and conclusions are those of the authors and are not necessarily endorsed by the United States Government.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1453
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	Author	Słysz, W.; Węgrzecki, M.; Bar, J.; Grabiec, P.; Górska, M.; Zwiller, V.; Latta, C.; Bohi, P.; Milostnaya, I.; Minaeva, O.; Antipov, A.; Okunev, O.; Korneev, A.; Smirnov, K.; Voronov, B.; Kaurova, N.; Gol’tsman, G.; Pearlman, A.; Cross, A.; Komissarov, I.; Verevkin, A.; Sobolewski, R.
	Title	Fiber-coupled single-photon detectors based on NbN superconducting nanostructures for practical quantum cryptography and photon-correlation studies			Type	Journal Article
	Year	2006	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	88	Issue	26	Pages	261113 (1 to 3)
	Keywords	SSPD, SNSPD
	Abstract	We have fabricated and tested a two-channel single-photon detector system based on two fiber-coupled superconducting single-photon detectors (SSPDs). Our best device reached the system quantum efficiency of 0.3% in the 1540-nm telecommunication wavelength with a fiber-to-detector coupling factor of about 30%. The photoresponse consisted of 2.5-ns-wide voltage pulses with a rise time of 250ps and timing jitter below 40ps. The overall system response time, measured as a second-order, photon cross-correlation function, was below 400ps. Our SSPDs operate at 4.2K inside a liquid-helium Dewar, but their optical fiber inputs and electrical outputs are at room temperature. Our two-channel detector system should find applications in practical quantum cryptography and in antibunching-type quantum correlation measurements. The authors would like to thank Dr. Marc Currie for his assistance in early time-resolved photoresponse measurements and Professor Atac Imamoglu for his support. This work was supported by the Polish Ministry of Science under Project No. 3 T11B 052 26 (Warsaw), RFBR 03-02-17697 and INTAS 03-51-4145 grants (Moscow), CRDF Grant No. RE2-2531-MO-03 (Moscow), RE2-2529-MO-03 (Moscow and Rochester), and US AFOSR FA9550-04-1-0123 (Rochester). Additional funding was provided by the grants from the MIT Lincoln Laboratory and BBN Technologies Corp.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1449
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	Author	Baselmans, J. J. A.; Baryshev, A.; Reker, S. F.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G.
	Title	Influence of the direct response on the heterodyne sensitivity of hot electron bolometer mixers			Type	Journal Article
	Year	2006	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
	Volume	100	Issue	8	Pages	084510 (1 to 7)
	Keywords	NbN HEB mixers
	Abstract	We present a detailed experimental study of the direct detection effect in a small volume (0.15μm×1μm×3.5nm) quasioptical NbN phonon cooled hot electron bolometer mixer at 673GHz. We find that the small signal noise temperature, relevant for an astronomical observation, is 20% lower than the noise temperature obtained using 300 and 77K calibration loads. In a separate set of experiments we show that the direct detection effect is caused by a combination of bias current reduction when switching from the 77 to the 300K load in combination with the bias current dependence of the receiver gain. The bias current dependence of the receiver gain is shown to be mainly caused by the current dependence of the mixer gain.
	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	0021-8979	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1442
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	Author	Kooi, J. W.; Baselmans, J. J. A.; Baryshev, A.; Schieder, R.; Hajenius, M.; Gao, J.R.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G.
	Title	Stability of heterodyne terahertz receivers			Type	Journal Article
	Year	2006	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
	Volume	100	Issue	6	Pages	064904 (1 to 9)
	Keywords	NbN HEB mixers
	Abstract	In this paper we discuss the stability of heterodyne terahertz receivers based on small volume NbN phonon cooled hot electron bolometers (HEBs). The stability of these receivers can be broken down in two parts: the intrinsic stability of the HEB mixer and the stability of the local oscillator (LO) signal injection scheme. Measurements show that the HEB mixer stability is limited by gain fluctuations with a 1∕f spectral distribution. In a 60MHz noise bandwidth this results in an Allan variance stability time of ∼0.3s. Measurement of the spectroscopic Allan variance between two intermediate frequency (IF) channels results in a much longer Allan variance stability time, i.e., 3s between a 2.5 and a 4.7GHz channel, and even longer for more closely spaced channels. This implies that the HEB mixer 1∕f noise is strongly correlated across the IF band and that the correlation gets stronger the closer the IF channels are spaced. In the second part of the paper we discuss atmospheric and mechanical system stability requirements on the LO-mixer cavity path length. We calculate the mixer output noise fluctuations as a result of small perturbations of the LO-mixer standing wave, and find very stringent mechanical and atmospheric tolerance requirements for receivers operating at terahertz frequencies.
	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	0021-8979	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1444
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	Author	Kerman, A. J.; Dauler, E. A.; Yang, J. K. W.; Rosfjord, K. M.; Anant, V.; Berggren, K. K.; Gol’tsman, G. N.; Voronov, B. M.
	Title	Constriction-limited detection efficiency of superconducting nanowire single-photon detectors			Type	Journal Article
	Year	2007	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	90	Issue	10	Pages	101110 (1 to 3)
	Keywords	SSPD, SNSPD
	Abstract	We investigate the source of the large variations in the observed detection efficiencies of superconducting nanowire single-photon detectors between many nominally identical devices. Through both electrical and optical measurements, we infer that these variations arise from “constrictions:” highly localized regions of the nanowires where the effective cross-sectional area for superconducting current is reduced. These constrictions limit the bias-current density to well below its critical value over the remainder of the wire, and thus prevent the detection efficiency from reaching the high values that occur in these devices when they are biased near the critical current density. This work is sponsored by the United States Air Force under Contract No. FA8721-05-C-0002.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1433
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	Author	Zinoni, C.; Alloing, B.; Li, L. H.; Marsili, F.; Fiore, A.; Lunghi, L.; Gerardino, A.; Vakhtomin, Y. B.; Smirnov, K. V.; Gol’tsman, G. N.
	Title	Single-photon experiments at telecommunication wavelengths using nanowire superconducting detectors			Type	Journal Article
	Year	2007	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	91	Issue	3	Pages	031106 (1 to 3)
	Keywords	SSPD, SNSPD, APD
	Abstract	The authors report fiber-coupled superconducting single-photon detectors with specifications that exceed those of avalanche photodiodes, operating at telecommunication wavelength, in sensitivity, temporal resolution, and repetition frequency. The improved performance is demonstrated by measuring the intensity correlation function g(2)(τ) of single-photon states at 1300nm produced by single semiconductor quantum dots. This work was supported by Swiss National Foundation through the “Professeur borsier” and NCCR Quantum Photonics program, FP6 STREP “SINPHONIA” (Contract No. NMP4-CT-2005-16433), IP “QAP” (Contract No. 15848), NOE “ePIXnet,” and the Italian MIUR-FIRB program.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes	Erratum: 1395			Approved	no
	Call Number				Serial	1396
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	Author	Gao, J. R.; Hajenius, M.; Tichelaar, F. D.; Klapwijk, T. M.; Voronov, B.; Grishin, E.; Gol’tsman, G.; Zorman, C. A.; Mehregany, M.
	Title	Monocrystalline NbN nanofilms on a 3C-SiC∕Si substrate			Type	Journal Article
	Year	2007	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	91	Issue	6	Pages	062504 (1 to 3)
	Keywords	NbN films, nanofilms
	Abstract	The authors have realized NbN (100) nanofilms on a 3C-SiC (100)/Si(100) substrate by dc reactive magnetron sputtering at 800°C. High-resolution transmission electron microscopy (HRTEM) is used to characterize the films, showing a monocrystalline structure and confirming epitaxial growth on the 3C-SiC layer. A film ranging in thickness from 3.4to4.1nm shows a superconducting transition temperature of 11.8K, which is the highest reported for NbN films of comparable thickness. The NbN nano-films on 3C-SiC offer a promising alternative to improve terahertz detectors. For comparison, NbN nanofilms grown directly on Si substrates are also studied by HRTEM. The authors acknowledge S. V. Svetchnikov at National Centre for HRTEM at Delft, who prepared the specimens for HRTEM inspections. This work was supported by the EU through RadioNet and INTAS.
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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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1425
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	Author	Ejrnaes, M.; Cristiano, R.; Quaranta, O.; Pagano, S.; Gaggero, A.; Mattioli, F.; Leoni, R.; Voronov, B.; Gol’tsman, G.
	Title	A cascade switching superconducting single photon detector			Type	Journal Article
	Year	2007	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	91	Issue	26	Pages	262509 (1 to 3)
	Keywords	SSPD, SNSPD, parallel-wire
	Abstract	We have realized superconducting single photon detectors with reduced inductance and increased signal pulse amplitude. The detectors are based on a parallel connection of ultrathin NbN nanowires with a common bias inductance. When properly biased, an absorbed photon induces a cascade switch of all the parallel wires generating a signal pulse amplitude of 2mV. The parallel wire configuration lowers the detector inductance and reduces the response time well below 1ns. This work was performed in the framework of the EU project “SINPHONIA” NMP4-CT-2005-016433.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1418
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	Author	Zinoni, C.; Alloing, B.; Li, L. H.; Marsili, F.; Fiore, A.; Lunghi, L.; Gerardino, A.; Vakhtomin, Y. B.; Smirnov, K. V.; Gol’tsman, G. N.
	Title	Erratum: “Single photon experiments at telecom wavelengths using nanowire superconducting detectors” [Appl. Phys. Lett. 91, 031106 (2007)]			Type	Journal Article
	Year	2010	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	96	Issue	8	Pages	089901
	Keywords	SSPD, SNSPD, erratum
	Abstract	A calculation error was made in the original publication of this letter. The error was in the calculation of the noise equivalent power (NEP) values for the avalanche photodiode detector (APD) and the superconducting single photon detector (SSPD), the incorrect values were plotted on the right axis in Fig. 1(b). The correct NEP values were calculated with the same equation reported in the original letter and the revised Fig. 1(b) is shown below. The other conclusions of the paper remain unaltered.
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	Language		Summary Language		Original Title
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	Series Volume		Series Issue		Edition
	ISSN	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1395
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	Author	Maingault, L.; Tarkhov, M.; Florya, I.; Semenov, A.; Espiau de Lamaëstre, R.; Cavalier, P.; Gol’tsman, G.; Poizat, J.-P.; Villégier, J.-C.
	Title	Spectral dependency of superconducting single photon detectors			Type	Journal Article
	Year	2010	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
	Volume	107	Issue	11	Pages	116103 (1 to 3)
	Keywords	NbN SSPD, SNSPD
	Abstract	We investigate the effect of varying both incoming optical wavelength and width of NbN nanowires on the superconducting single photon detectors (SSPD) detection efficiency. The SSPD are current biased close to critical value and temperature fixed at 4.2 K, far from transition. The experimental results are found to verify with a good accuracy predictions based on the “hot spot model,” whose size scales with the absorbed photon energy. With larger optical power inducing multiphoton detection regime, the same scaling law remains valid, up to the three-photon regime. We demonstrate the validity of applying a limited number of measurements and using such a simple model to reasonably predict any SSPD behavior among a collection of nanowire device widths at different photon wavelengths. These results set the basis for designing efficient single photon detectors operating in the infrared (2–5 μm range). This work was supported by European projects FP6 STREP “SINPHONIA” (Contract No. NMP4-CT-2005-16433) and IP “QAP” (Contract No. 15848).
	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	0021-8979	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1392
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	Author	Elvira, D.; Michon, A.; Fain, B.; Patriarche, G.; Beaudoin, G.; Robert-Philip, I.; Vachtomin, Y.; Divochiy, A. V.; Smirnov, K. V.; Gol’tsman, G. N.; Sagnes, I.; Beveratos, A.
	Title	Time-resolved spectroscopy of InAsP/InP(001) quantum dots emitting near 2 μm			Type	Journal Article
	Year	2010	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	97	Issue	13	Pages	131907 (1 to 3)
	Keywords	SSPD, SNSPD, InAsP/InP quantum dots
	Abstract	By using superconducting single photon detectors, we perform time-resolved characterization of a small ensemble of InAsP/InP quantum dots grown by metal organic vapor phase epitaxy, emitting at wavelengths between 1.6 and 2.2 μm. We demonstrate that alloying phosphorus with InAs allows to shift the emission wavelength toward higher wavelengths, while keeping the high optical quality of these quantum dots at room temperature, with no decrease in their radiative lifetime. This work was partially supported by Russian Ministry of Science and Education: Federal State Program “Scientific and Educational Cadres of Innovative” state Contract Nos. 02.740.0228, 14.740.11.0343, 14.740.11.0269, and P931, and RFBR Project No. 09-02-12364.
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1238
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	Author	Nebosis, R. S.; Steinke, R.; Lang, P. T.; Schatz, W.; Heusinger, M. A.; Renk, K. F.; Gol’tsman, G. N.; Karasik, B. S.; Semenov, A. D.; Gershenzon, E. M.
	Title	Picosecond YBa₂Cu₃O_7−δdetector for far‐infrared radiation			Type	Journal Article
	Year	1992	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
	Volume	72	Issue	11	Pages	5496-5499
	Keywords	YBCO HTS detectors
	Abstract	We report on a picosecond YBa2Cu3O7−δ detector for far‐infrared radiation. The detector, consisting of a current carrying structure cooled to liquid‐nitrogen temperature, was studied by use of ultrashort laser pulses from an optically pumped far‐infrared laser in the frequency range from 25 to 215 cm−1. We found that the sensitivity (1 mV/W) was almost constant in this frequency range. We estimated a noise equivalent power of less than 5×10−7 W Hz−1/2. Taking into account the results of a mixing experiment (in the frequency range from 4 to 30 cm−1) we suggest that the response time of the detector was few picoseconds.
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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	0021-8979	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1668
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	Author	Danerud, M.; Winkler, D.; Lindgren, M.; Zorin, M.; Trifonov, V.; Karasik, B. S.; Gol’tsman, G. N.; Gershenzon, E. M.
	Title	Nonequilibrium and bolometric photoresponse in patterned YBa₂Cu₃O_7−δ thin films			Type	Journal Article
	Year	1994	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
	Volume	76	Issue	3	Pages	1902-1909
	Keywords	YBCO HTS HEB detector, nonequilibrium response
	Abstract	Epitaxial laser deposited YBa2Cu3O7−δ films of ∼50 nm thickness were patterned into detectors consisting of ten parallel 1 μm wide strips in order to study nonequilibrium and bolometric effects. Typically, the patterned samples had critical temperatures around 86 K, transition widths around 2 K and critical current densities above 1×106A/cm2 at 77 K. Pulsed laser measurements at 0.8 μm wavelength (17 ps full width at half maximum) showed a ∼30 ps response, attributed to electron heating, followed by a slower bolometric decay. Amplitude modulation in the band fmod=100 kHz–10 GHz of a laser with wavelength λ=0.8 μm showed two different thermal relaxations in the photoresponse. Phonon escape from the film (∼3 ns) is the limiting process, followed by heat diffusion in the substrate. Similar relaxations were also seen for λ=10.6 μm. The photoresponse measurements were made with the film in the resistive state and extended into the normal state. These states were created by supercritical bias currents. Measurements between 75 and 95 K (i.e., from below to above Tc) showed that the photoresponse was proportional to dR/dT for fmod=1 MHz and 4 GHz. The fast response is limited by the electron‐phonon scattering time, estimated to 1.8 ps from experimental data. The responsivity both at 0.8 and 10.6 μm wavelength was ∼1.2 V/W at fmod=1 GHz and the noise equivalent power was calculated to 1.5×10−9 WHz−1/2 for the fast response.
	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	0021-8979	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1637
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	Author	Karasik, B. S.; Zorin, M. A.; Milostnaya, I. I.; Elantev, A. I.; Gol’tsman, G. N.; Gershenzon, E. M.
	Title	Subnanosecond switching of YBaCuO films between superconducting and normal states induced by current pulse			Type	Journal Article
	Year	1995	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
	Volume	77	Issue	8	Pages	4064-4070
	Keywords	YBCO HTS switches
	Abstract	A study is reported of the current switching in high‐quality YBaCuO films deposited onto NdGaO3 and ZrO2 substrates between superconducting (S) and normal (N) states. The films 60–120 nm thick prepared by laser ablation were structured into single strips between gold contacts. The time dependence of the resistance after application of the voltage step to the film was monitored. Experiment performed within certain ranges of voltage amplitudes and temperatures has shown the occurrence of the fast stage (shorter than 400 ps) both in S‐N and N‐S transitions. A fraction of the film resistance changing within this stage in the S‐N transition increases with the current amplitude. A subnanosecond N‐S stage becomes more pronounced for shorter pulses. The fast switching is followed by the much slower change of resistance. The mechanism of switching is discussed in terms of the hot‐electron phenomena in YBaCuO. The contributions of other thermal processes (e.g., a phonon escape from the film, a heat diffusion in the film and substrate, a resistive domain formation) in the subsequent stage of the resistance dynamic have been also discussed. The basic limiting characteristics (average dissipated power, energy needed for switching, maximum repetition rate) of a picosecond switch which is proposed to be developed are estimated.
	Address
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	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1623
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	Author	Kawamura, J.; Blundell, R.; Tong, C.‐yu E.; Gol’tsman, G.; Gershenzon, E.; Voronov, B.
	Title	Performance of NbN lattice‐cooled hot‐electron bolometric mixers			Type	Journal Article
	Year	1996	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
	Volume	80	Issue	7	Pages	4232-4234
	Keywords	NbN HEB mixers
	Abstract	The heterodyne performance of lattice‐cooled hot‐electron bolometric mixers is measured at 200 GHz. Superconducting thin‐film niobium nitride strips with ∼5 nm thickness are used as waveguide mixer elements. A double‐sideband receiver noise temperature of 750 K at 244 GHz is measured at an intermediate frequency centered at 1.5 GHz with 500 MHz bandwidth and with 4.2 K device temperature. The instantaneous bandwidth for this mixer is 1.6 GHz. The local oscillator power required by the mixer is about 0.5 μW. The mixer is linear to within 1 dB up to an input power level 6 dB below the local oscillator power. A receiver incorporating a hot‐electron bolometric mixer was used to detect molecular line emission in a laboratory gascell. This experiment unambiguously confirms that the receiver noise temperature determined from Y‐factor measurements reflects the true heterodyne sensitivity.
	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	0021-8979	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1607
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	Author	Rasulova, G. K.; Brunkov, P. N.; Pentin, I. V.; Egorov, A. Y.; Knyazev, D. A.; Andrianov, A. V.; Zakhar’in, A. O.; Konnikov, S. G.; Gol’tsman, G. N.
	Title	A weakly coupled semiconductor superlattice as a potential for a radio frequency modulated terahertz light emitter			Type	Journal Article
	Year	2012	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
	Volume	100	Issue	13	Pages	131104 (1 to 4)
	Keywords	semiconductor superlattice
	Abstract	The bolometer response to THz radiation from a weakly coupled GaAs/AlGaAs superlattice biased in the self-oscillations regime has been observed. The bolometer signal is modulated with the frequency equal to the fundamental frequency of superlattice self-oscillations. The frequency spectrum of the bolometer signal contains higher harmonics whose frequency is a multiple of fundamental frequency of self-oscillations. This work was supported by State Contracts Nos. 16.740.11.0044 and 16.552.11.7002 of Ministry of Education and Science of the Russian Federation. Structural characterization was made on the equipment of the Joint Research Centre «Material science and characterization in advanced technology» (Ioffe Institute, St. Petersburg, Russia).
	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	0003-6951	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1379
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	Author	Semenov, A. D.; Gol’tsman, G. N.
	Title	Nonthermal mixing mechanism in a diffusion-cooled hot-electron detector			Type	Journal Article
	Year	2000	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
	Volume	87	Issue	1	Pages	502-510
	Keywords	NbN HEB mixers, nonthermal
	Abstract	We present an analysis of a diffusion-cooled hot-electron detector fabricated from clean superconducting material with low transition temperature. The distinctive feature of a clean material, i.e., material with large electron mean free path, is a relatively weak inelastic electron scattering that is not sufficient for the establishment of an elevated thermodynamic electron temperature when the detector is subjected to irradiation. We propose an athermal model of a diffusion-cooled detector that relies on suppression of the superconducting energy gap by the actual dynamic distribution of excess quasiparticles. The resistive state of the device is caused by the electric field penetrating into the superconducting bridge from metal contacts. The dependence of the penetration length on the energy gap delivers the detection mechanism. The sources of the electric noise are equilibrium fluctuations of the number of thermal quasiparticles and frequency dependent shot noise. Using material parameters typical for A1, we evaluate performance of the device in the heterodyne regime at terahertz frequencies. Estimates show that the mixer may have a noise temperature of a few quantum limits and a bandwidth of a few tens of GHz, while the required local oscillator power is in the μW range due to ineffective suppression of the energy gap by quasiparticles with high energies.
	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	0021-8979	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1558
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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.
	Address
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	Language		Summary Language		Original Title
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	ISSN		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	ozhegov2010terahertz			Serial	1397
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	Author	Milostnaya, I.; Korneev, A.; Tarkhov, M.; Divochiy, A.; Minaeva, O.; Seleznev, V.; Kaurova, N.; Voronov, B.; Okunev, O.; Chulkova, G.; Smirnov, K.; Gol’tsman, G.
	Title	Superconducting single photon nanowire detectors development for IR and THz applications			Type	Journal Article
	Year	2008	Publication	J. Low Temp. Phys.	Abbreviated Journal	J. Low Temp. Phys.
	Volume	151	Issue	1-2	Pages	591-596
	Keywords	NbN SSPD, SNSPD
	Abstract	We present our progress in the development of superconducting single-photon detectors (SSPDs) based on meander-shaped nanowires made from few-nm-thick superconducting films. The SSPDs are operated at a temperature of 2–4.2 K (well below T c ) being biased with a current very close to the nanowire critical current at the operation temperature. To date, the material of choice for SSPDs is niobium nitride (NbN). Developed NbN SSPDs are capable of single photon counting in the range from VIS to mid-IR (up to 6 μm) with a record low dark counts rate and record-high counting rate. The use of a material with a low transition temperature should shift the detectors sensitivity towards longer wavelengths. We present state-of-the art NbN SSPDs as well as the results of our recent approach to expand the developed SSPD technology by the use of superconducting materials with lower T c , such as molybdenum rhenium (MoRe). MoRe SSPDs first were made and tested; a single photon response was obtained.
	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	0022-2291	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1244
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	Author	Tikhonov, V. V.; Polyakova, O. N.; Gol’tsman, G. N.; Dzardanov, A. L.; Boyarskiy, D. A.
	Title	Determination of dielectric properties of ore minerals in the microwave band			Type	Journal Article
	Year	2008	Publication	Radiophys. Quant. Electron.	Abbreviated Journal	Radiophys. Quant. Electron.
	Volume	51	Issue	12	Pages	966-974
	Keywords	ore complex permittivity, chalcopyrite, magnetite, sphalerite, labradorite
	Abstract	We consider a method for determining the complex dielectric permittivity of ore and nonmetal minerals in the microwave band of electromagnetic radiation. The results of measuring the reflectivity and transmittivity of chalcopyrite, magnetite, sphalerite, and labradorite samples in the frequency range 77–300 GHz are presented. A method for calculation of the complex dielectric permittivity of minerals on the basis of the obtained experimental data is proposed. The approximation formulas for calculation of the complex dielectric permittivity of the studied minerals are given.
	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	0033-8443	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1404
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	Author	Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Voronov, B. M.; Gol’tsman, G. N.; Gershenson, E. M.; Yngvesson, K. S.
	Title	Multiple Andreev reflection in hybrid AlGaAs/GaAs structures with superconducting NbN contacts			Type	Journal Article
	Year	1999	Publication	Semicond.	Abbreviated Journal	Semicond.
	Volume	33	Issue	5	Pages	551-554
	Keywords	2DEG, AlGaAs/GaAs heterostructures
	Abstract	The conductivity of hybrid microstructures with superconducting contacts made of niobium nitride to a semiconductor with a two-dimensional electron gas in a AlGaAs/GaAs heterostructure has been investigated. Distinctive features of the behavior of the conductivity indicate the presence of multiple Andreev reflection at scattering centers in the normal region near the superconductor-semiconductor boundary.
	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	1063-7826	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1571
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	Author	Men’shchikov, E. M.; Gogidze, I. G.; Sergeev, A. V.; Elant’ev, A. I.; Kuminov, P. B.; Gol’tsman, G. N.; Gershenzon, E. M.
	Title	Superconducting fast detector based on the nonequilibrium inductance response of a film of niobium nitride			Type	Journal Article
	Year	1997	Publication	Tech. Phys. Lett.	Abbreviated Journal	Tech. Phys. Lett.
	Volume	23	Issue	6	Pages	486-488
	Keywords	NbN KID
	Abstract	A new type of fast detector is proposed, whose operation is based on the variation of the kinetic inductance of a superconducting film caused by nonequilibrium quasiparticles created by the electromagnetic radiation. The speed of the detector is determined by the rate of multiplication of photo-excited quasiparticles, and is nearly independent of the temperature, being less than 1 ps for NbN. Models based on the Owen-Scalapino scheme give a good description of the experimentally determined dependence of the power-voltage sensitivity of the detector on the modulation frequency. The lifetime of the quasiparticles is determined, and it is shown that the reabsorption of nonequilibrium phonons by the condensate has a substantial effect even in ultrathin NbN films 5 nm thick, and results in the maximum possible quantum yield. A low concentration of equilibrium quasiparticles and a high quantum yield result in a detectivity D=1012 W−1·Hz1/2 at a temperature T=4.2 K and D=1016 W−1·cm· Hz1/2 at T=1.6 K.
	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	1063-7850	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1593
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	Author	Gol’tsman, G. N.; Smirnov, K. V.
	Title	Electron-phonon interaction in a two-dimensional electron gas of semiconductor heterostructures at low temperatures			Type	Journal Article
	Year	2001	Publication	Jetp Lett.	Abbreviated Journal	Jetp Lett.
	Volume	74	Issue	9	Pages	474-479
	Keywords	2DEG, AlGaAs/GaAs heterostructures
	Abstract	Theoretical and experimental works devoted to studying electron-phonon interaction in the two-dimensional electron gas of semiconductor heterostructures at low temperatures in the case of strong heating in an electric field under quasi-equilibrium conditions and in a quantizing magnetic field perpendicular to the 2D layer are considered.
	Address
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	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
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	Series Volume		Series Issue		Edition
	ISSN	0021-3640	ISBN		Medium
	Area		Expedition		Conference
	Notes	По итогам проектов российского фонда фундаментальных исследований. Проект РФФИ # 98-02-16897 Электрон-фононное взаимодействие в двумерном электронном газе полупроводниковых гетероструктур при низких температурах			Approved	no
	Call Number				Serial	1541
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	Author	Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Gol’tsman, G. N.; Gershenzon, E. M.; Ingvesson, K. S.
	Title	Direct measurements of energy relaxation times on an AlGaAs/GaAs heterointerface in the range 4.2–50 K			Type	Journal Article
	Year	1996	Publication	JETP Lett.	Abbreviated Journal	JETP Lett.
	Volume	64	Issue	5	Pages	404-409
	Keywords	2DEG, AlGaAs/GaAs heterostructures
	Abstract	The temperature dependence of the energy relaxation time τe (T) of a two-dimensional electron gas at an AlGaAs/GaAs heterointerface is measured under quasiequilibrium conditions in the region of the transition from scattering by acoustic phonons to scattering with the participation of optical phonons. The temperature interval of constant τe, where scattering by the deformation potential predominates, is determined. In the preceding, low-temperature region, where piezoacoustic and deformation-potential-induced scattering processes coexist, τ e decreases slowly with increasing temperature. Optical phonons start to participate in the scattering processes at T∼25 K (the characteristic phonon lifetime was equal to τLOτ4.5 ps). The energy losses calculated from the τe data in a model with an effective nonequilibrium electron temperature agree with the published data obtained under strong heating conditions.
	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	0021-3640	ISBN		Medium
	Area		Expedition		Conference
	Notes	http://jetpletters.ru/ps/981/article_14955.shtml (“Прямые измерения времен энергетической релаксации на гетерогранице AlGaAs/GaAs в диапазоне 4.2 – 50 К”)			Approved	no
	Call Number				Serial	1608
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	Author	Smirnov, K. V.; Ptitsina, N. G.; Vakhtomin, Y. B.; Verevkin, A. A.; Gol’tsman, G. N.; Gershenzon, E. M.
	Title	Energy relaxation of two-dimensional electrons in the quantum Hall effect regime			Type	Journal Article
	Year	2000	Publication	JETP Lett.	Abbreviated Journal	JETP Lett.
	Volume	71	Issue	1	Pages	31-34
	Keywords	2DEG, GaAs/AlGaAs heterostructures
	Abstract	The mm-wave spectroscopy with high temporal resolution is used to measure the energy relaxation times τe of 2D electrons in GaAs/AlGaAs heterostructures in magnetic fields B=0–4 T under quasi-equilibrium conditions at T=4.2 K. With increasing B, a considerable increase in τe from 0.9 to 25 ns is observed. For high B and low values of the filling factor ν, the energy relaxation rate τ −1e oscillates. The depth of these oscillations and the positions of maxima depend on the filling factor ν. For ν>5, the relaxation rate τ −1e is maximum when the Fermi level lies in the region of the localized states between the Landau levels. For lower values of ν, the relaxation rate is maximum at half-integer values of τ −1e when the Fermi level is coincident with the Landau level. The characteristic features of the dependence τ −1e (B) are explained by different contributions of the intralevel and interlevel electron-phonon transitions to the process of the energy relaxation of 2D electrons.
	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	0021-3640	ISBN		Medium
	Area		Expedition		Conference
	Notes	http://jetpletters.ru/ps/899/article_13838.shtml (“Энергетическая релаксация двумерных электронов в области квантового эффекта Холла”)			Approved	no
	Call Number				Serial	1559
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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.
	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	0021-3640	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1377
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	Author	Shangina, E. L.; Smirnov, K. V.; Morozov, D. V.; Kovalyuk, V. V.; Gol’tsman, G. N.; Verevkin, A. A.; Toropov, A. I.
	Title	Frequency bandwidth and conversion loss of a semiconductor heterodyne receiver with phonon cooling of two-dimensional electrons			Type	Journal Article
	Year	2010	Publication	Semicond.	Abbreviated Journal	Semicond.
	Volume	44	Issue	11	Pages	1427-1429
	Keywords	2DEG, AlGaAs/GaAs heterostructures mixers
	Abstract	The temperature and concentration dependences of the frequency bandwidth of terahertz heterodyne AlGaAs/GaAs detectors based on hot electron phenomena with phonon cooling of two-dimensional electrons have been measured by submillimeter spectroscopy with a high time resolution. At a temperature of 4.2 K, the frequency bandwidth at a level of 3 dB (f 3 dB) is varied from 150 to 250 MHz with a change in the concentration n s according to the power law f 3dB ∝ n −0.5 s due to the dominant contribution of piezoelectric phonon scattering. The minimum conversion loss of the semiconductor heterodyne detector is obtained in structures with a high carrier mobility (μ > 3 × 105 cm2 V−1 s−1 at 4.2 K).
	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	1063-7826	ISBN		Medium
	Area		Expedition		Conference
	Notes	Полоса и потери преобразования полупроводникового смесителя с фононным каналом охлаждения двумерных электронов			Approved	no
	Call Number				Serial	1216
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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
	Notes				Approved	no
	Call Number				Serial	1378
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	Author	Polyakova, O. N.; Tikhonov, V. V.; Dzardanov, A. L.; Boyarskii, D. A.; Gol’tsman, G. N.
	Title	Dielectric characteristics of ore minerals in a 10–40 GHz frequency range			Type	Journal Article
	Year	2008	Publication	Tech. Phys. Lett.	Abbreviated Journal	Tech. Phys. Lett.
	Volume	34	Issue	11	Pages	967-970
	Keywords	ore minerals, complex permittivity, sphalerite, magnetite, labradorite
	Abstract	A new approach to investigation of the complex dielectric permittivity of both nonmetallic and ore minerals in the microwave frequency range is proposed. Using this approach, data on the complex permittivity of sphalerite, magnetite, and labradorite in a 10–40 GHz frequency range have been obtained for the first time. A method is proposed for calculating the complex permittivity from experimentally measured frequency dependences of the reflection and transmission coefficients of a plane-parallel plate of a given mineral. Approximate expressions that can be used for calculations of the complex refractive index and permittivity of minerals are presented.
	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	1063-7850	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1406
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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.
	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	1063-7850	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1390
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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.
	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	1063-7850	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1389
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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.
	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	1064-2269	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1400
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	Author	Shangina, E. L.; Smirnov, K. V.; Morozov, D. V.; Kovalyuk, V. V.; Gol’tsman, G. N.; Verevkin, A. A.; Toropov, A. I.
	Title	Concentration dependence of the intermediate frequency bandwidth of submillimeter heterodyne AlGaAs/GaAs nanostructures			Type	Journal Article
	Year	2010	Publication	Bull. Russ. Acad. Sci. Phys.	Abbreviated Journal	Bull. Russ. Acad. Sci. Phys.
	Volume	74	Issue	1	Pages	100-102
	Keywords	2DEG AlGaAs/GaAs heterostructures, THz heterodyne detectors, IF bandwidth
	Abstract	The concentration dependence of the intermediate frequency bandwidth of heterodyne AlGaAs/GaAs detectors with 2D electron gas is measured using submillimeter spectroscopy with high time resolution at T= 4.2 K. The intermediate frequency bandwidth f3dBfalls from 245 to 145 MHz with increasing concentration of 2D electrons n s = (1.6-6.6) × 10[su11] cm-2. The dependence f3dB ≈ n s – 0.04±is observed in the studied concentration range; this dependence is determined by electron scattering by the deformation potential of acoustic phonons and piezoelectric scattering.
	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	1062-8738	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1217
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	Author	Kurochkin, V. L.; Zverev, A. V.; Kurochkin, Y. V.; Ryabtsev, I. I.; Neizvestnyi, I. G.; Ozhegov, R. V.; Gol’tsman, G. N.; Larionov, P. A.
	Title	Long-distance fiber-optic quantum key distribution using superconducting detectors			Type	Conference Article
	Year	2015	Publication	Proc. Optoelectron. Instrum.	Abbreviated Journal	Proc. Optoelectron. Instrum.
	Volume	51	Issue	6	Pages	548-552
	Keywords	QKD, SSPD, SNSPD
	Abstract	This paper presents the results of experimental studies on quantum key distribution in optical fiber using superconducting detectors. Key generation was obtained on an experimental setup based on a self-compensation optical circuit with an optical fiber length of 101.1 km. It was first shown that photon polarization encoding can be used for quantum key distribution in optical fiber over a distance in excess of 300 km.
	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	8756-6990	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1342
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	Author	Somani, S.; Kasapi, S.; Wilsher, K.; Lo, W.; Sobolewski, R.; Gol’tsman, G.
	Title	New photon detector for device analysis: Superconducting single-photon detector based on a hot electron effect			Type	Journal Article
	Year	2001	Publication	J. Vac. Sci. Technol. B	Abbreviated Journal	J. Vac. Sci. Technol. B
	Volume	19	Issue	6	Pages	2766-2769
	Keywords	NbN SSPD, SNSPD
	Abstract	A novel superconducting single-photon detector (SSPD), intrinsically capable of high quantum efficiency (up to 20%) over a wide spectral range (ultraviolet to infrared), with low dark counts (<1 cps), and fast (<40 ps) timing resolution, is described. This SSPD has been used to perform timing measurements on complementary metal–oxide–semiconductor integrated circuits (ICs) by detecting the infrared light emission from switching transistors. Measurements performed from the backside of a 0.13 μm geometry flip–chip IC are presented. Other potential applications for this detector are in telecommunications, quantum cryptography, biofluorescence, and chemical kinetics.
	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	0734211X	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1542
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	Author	Sergeev, A. V.; Semenov, A. D.; Kouminov, P.; Trifonov, V.; Goghidze, I. G.; Karasik, B. S.; Gol’tsman, G. N.; Gershenzon, E. M.
	Title	Transparency of a YBa2Cu3O7-film/substrate interface for thermal phonons measured by means of voltage response to radiation			Type	Journal Article
	Year	1994	Publication	Phys. Rev. B Condens. Matter.	Abbreviated Journal	Phys. Rev. B Condens. Matter.
	Volume	49	Issue	13	Pages	9091-9096
	Keywords	YBCO films
	Abstract	The transparency of a film/substrate interface for thermal phonons was investigated for YBa2Cu3O7 thin films deposited on MgO, Al2O3, LaAlO3, NdGaO3, and ZrO2 substrates. Both voltage response to pulsed-visible and to continuously modulated far-infrared radiation show two regimes of heat escape from the film to the substrate. That one dominated by the thermal boundary resistance at the film/substrate interface provides an initial exponential decay of the response. The other one prevailing at longer times or smaller modulation frequencies causes much slower decay and is governed by phonon diffusion in the substrate. The transparency of the boundary for phonons incident from the film on the substrate and also from the substrate on the film was determined separately from the characteristic time of the exponential decay and from the time at which one regime was changed to the other. Taking into account the specific heat of optical phonons and the temperature dependence of the group velocity of acoustic phonons, we show that the body of experimental data agrees with acoustic mismatch theory rather than with the model that assumes strong diffusive scattering of phonons at the interface.
	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	0163-1829	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:10009690			Approved	no
	Call Number				Serial	1648
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	Author	Zhang, J.; Pearlman, A.; Slysz, W.; Verevkin, A.; Sobolewski, R.; Okunev, O.; Korneev, A.; Kouminov, P.; Smirnov, K.; Chulkova, G.; Gol’tsman, G. N.; Lo, W.; Wilsher, K.
	Title	Infrared picosecond superconducting single-photon detectors for CMOS circuit testing			Type	Conference Article
	Year	2003	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
	Volume		Issue		Pages	Cmv4
	Keywords	NbN SSPD; SNSPD; Infrared; Quantum detectors; Electron beam lithography; Infrared detectors; Infrared radiation; Quantum efficiency; Single photon detectors; Superconductors
	Abstract	Novel, NbN superconducting single-photon detectors have been developed for ultrafast, high quantum efficiency detection of single quanta of infrared radiation. Our devices have been successfully implemented in a commercial VLSI CMOS circuit testing system.
	Address
	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	Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference
	Notes				Approved	no
	Call Number				Serial	1518
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	Author	Verevkin, A.; Slysz, W.; Pearlman, A.; Zhang, J.; Sobolewski, R.; Okunev, O.; Korneev, A.; Kouminov, P.; Smirnov, K.; Chulkova, G.; Gol’tsman, G. N.; Currie, M.
	Title	Real-time GHz-rate counting of infrared photons using nanostructured NbN superconducting detectors			Type	Conference Article
	Year	2003	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
	Volume		Issue		Pages	CThM8
	Keywords	NbN SSPD; SNSPD; Infrared; Quantum detectors; Detectors; Photon counting; Quantum communications; Quantum cryptography; Single photon detectors; Superconductors
	Abstract	We demonstrate that our ultrathin, nanometer-width NbN superconducting single-photon detectors are capable of above 1-GHz-frequency, real-time counting of near-infrared photons. The measured system jitter of the detector is below 15 ps.
	Address
	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	Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference
	Notes				Approved	no
	Call Number				Serial	1517
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	Author	Dauler, E. A.; Kerman, A. J.; Robinson, B. S.; Yang, J. K. W.; Voronov, B. M.; Gol’tsman, G. N.; Berggren, K. K.
	Title	Achieving high counting rates in superconducting nanowire single-photon detectors			Type	Conference Article
	Year	2006	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
	Volume		Issue		Pages	JTuD3 (1 to 2)
	Keywords	SSPD; SNSPD; Detectors; Photodetectors; Quantum optics; Quantum detectors; Photon counting; Photons; Pulse shaping; Quantum communications; Single photon detectors; Superconductors
	Abstract	Kinetic inductance is determined to be the primary limitation to the counting rate of superconducting nanowire single-photon counters. Approaches for overcoming this limitation will be discussed.
	Address
	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	Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies
	Notes				Approved	no
	Call Number				Serial	1451
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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.
	Address
	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
	Notes				Approved	no
	Call Number				Serial	1345
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	Author	Verevkin, A.; Williams, C.; Gol’tsman, G. N.; Sobolewski, R.; Gilbert, G.
	Title	Single-photon superconducting detectors for practical high-speed quantum cryptography			Type	Miscellaneous
	Year	2001	Publication	OFCC/ICQI	Abbreviated Journal	OFCC/ICQI
	Volume		Issue		Pages	Pa3
	Keywords	NbN SSPD, SNSPD, QKD, quantum cryptography
	Abstract	We have developed an ultrafast superconducting single-photon detector with negligible dark counting rate. The detector is based on an ultrathin, submicron-wide NbN meander-type stripe and can detect individual photons in the visible to near-infrared wavelength range at a rate of at least 10 Gb/s. The above counting rate allows us to implement the NbN device to unconditionally secret quantum key distRochester, New Yorkribution in a practical, high-speed system using real-time Vernam enciphering.
	Address	Rochester, New York
	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	Optical Fiber Communication Conference and International Conference on Quantum Information
	Notes	-- from poster session.			Approved	no
	Call Number				Serial	1544
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	Author	Sobolewski, R.; Verevkin, A.; Gol’tsman, G. N.
	Title	Superconducting optical single-photon detectors			Type	Conference Article
	Year	2004	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
	Volume		Issue		Pages	IThD1
	Keywords	SSPD, QE, jitter, dark counts
	Abstract	We review the development of superconducting single-photon detectors. The devices are characterized by experimental quantum efficiency of ~8% for infrared photons, counting rate ~2 GHz, 18 ps jitter, and <0.01 per second dark counts.
	Address
	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
	Notes				Approved	no
	Call Number	Sobolewski:04			Serial	1489
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	Author	Zinoni, C.; Alloing, B.; Li, L. H.; Marsili, F.; Fiore, A.; Lunghi, L.; Gerardino, A.; Vakhtomin, Y. B.; Smirnov, K. V.; Gol’tsman, G. N.
	Title	Single-photonics at telecom wavelengths using nanowire superconducting single photon detectors			Type	Conference Article
	Year	2007	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
	Volume		Issue		Pages	QTuF6 (1 to 2)
	Keywords	SSPD, SNSPD
	Abstract	Novel single-photon detectors based on NbN superconducting nanostructures promise orders-of- magnitude improvement over InGaAs APDs. We demonstrate this improved performance for the first time by measuring the g(2)(τ) on single photon states produced by a quantum dot at telecom wavelength.
	Address
	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	Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies
	Notes				Approved	no
	Call Number	Zinoni:07			Serial	1432
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	Author	Marsili, F.; Bitauld, D.; Divochiy, A.; Gaggero, A.; Leoni, R.; Mattioli, F.; Korneev, A.; Seleznev, V.; Kaurova, N.; Minaeva, O.; Gol’tsman, G.; Lagoudakis, K.G.; Benkahoul, M.; Lévy, F.; Fiore, A.
	Title	Superconducting nanowire photon number resolving detector at telecom wavelength			Type	Conference Article
	Year	2008	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
	Volume		Issue		Pages	Qmj1 (1 to 2)
	Keywords	PNR SSPD; SNSPD; Detectors; Infrared; Low light level; Diode lasers; Photons; Scanning electron microscopy; Superconductors; Ti:sapphire lasers
	Abstract	We demonstrate a photon-number-resolving (PNR) detector, based on parallel superconducting nanowires, capable of resolving up to 5 photons in the telecommunication wavelength range, with sensitivity and speed far exceeding existing approaches.
	Address
	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	978-1-55752-859-9	Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	Marsili:08			Serial	1243
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	Author	Gol’tsman, G.N.
	Title	Overview of recent results for superconducting NbN terahertz and optical detectors and mixers			Type	Miscellaneous
	Year	2014	Publication	SM2 – Seminar on Terahertz Photonics	Abbreviated Journal
	Volume		Issue		Pages	0562
	Keywords	NbN SSPD, SNSPD, HEB
	Abstract	We present our recent achievements in the development of sensitive and ultrafast thin-film superconducting sensors: hot-electron bolometers (HEB), HEB-mixers for terahertz range and infrared single-photon counters. These sensors have already demonstrated a performance that makes them devices-of-choice for many terahertz and optical applications.
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	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
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	Notes				Approved	no
	Call Number				Serial	1746
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	Author	Słysz, W.; Wegrzecki, M.; Bar, J.; Grabiec, P.; Górska, M.; Zwiller, V.; Latta, C.; Böhi, P.; Pearlman, A.J.; Cross, A.S.; Pan, D.; Kitaygorsky, J.; Komissarov, I.; Verevkin, A.; Milostnaya, I.; Korneev, A.; Minayeva, O.; Chulkova, G.; Smirnov, K.; Voronov, B.; Gol’tsman, G.N.; Sobolewski, R.
	Title	Fibre-coupled, single photon detector based on NbN superconducting nanostructures for quantum communications			Type	Journal Article
	Year	2007	Publication	J. Modern Opt.	Abbreviated Journal	J. Modern Opt.
	Volume	54	Issue	2-3	Pages	315-326
	Keywords	NbN SSPD, SNSPD
	Abstract	We present a novel, two-channel, single photon receiver based on two fibre-coupled, NbN, superconducting, single photon detectors (SSPDs). The SSPDs are nanostructured superconducting meanders and are known for ultrafast and efficient detection of visible-to-infrared photons. Coupling between the NbN detector and optical fibre was achieved using a micromechanical photoresist ring placed directly over the SSPD, holding the fibre in place. With this arrangement, we obtained coupling efficiencies up to ∼30%. Our experimental results showed that the best receiver had a near-infrared system quantum efficiency of 0.33% at 4.2 K. The quantum efficiency increased exponentially with the photon energy increase, reaching a few percent level for visible-light photons. The photoresponse pulses of our devices were limited by the meander high kinetic inductance and had the rise and fall times of approximately 250 ps and 5 ns, respectively. The receiver's timing jitter was in the 37 to 58 ps range, approximately 2 to 3 times larger than in our older free-space-coupled SSPDs. We stipulate that this timing jitter is in part due to optical fibre properties. Besides quantum communications, the two-detector arrangement should also find applications in quantum correlation experiments.
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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	0950-0340	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1434
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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.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes	Duplicated as 641			Approved	no
	Call Number				Serial	1388
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	Author	Murphy, A.; Semenov, A.; Korneev, A.; Korneeva, Y.; Gol’tsman, G.; Bezryadin, A.
	Title	Dark counts initiated by macroscopic quantum tunneling in NbN superconducting photon detectors			Type	Miscellaneous
	Year	2014	Publication	arXiv	Abbreviated Journal
	Volume		Issue		Pages
	Keywords	NbN SSPD
	Abstract	We perform measurements of the switching current distributions of three w = 120 nm wide, 4 nm thick NbN superconducting strips which are used for single-photon detectors. These strips are much wider than the diameter the vortex cores, so they are classified as quasi-two-dimensional (quasi-2D). We discover evidence of macroscopic quantum tunneling by observing the saturation of the standard deviation of the switching distributions at temperatures around 2 K. We analyze our results using the Kurkijarvi-Garg model and find that the escape temperature also saturates at low temperatures, confirming that at sufficiently low temperatures, macroscopic quantum tunneling is possible in quasi-2D strips and can contribute to dark counts observed in single photon detectors.
	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
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	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	murphy2014dark			Serial	1356
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	Author	Arutyunov, K. Y.; Ramos-Álvarez, A.; Semenov, A. V.; Korneeva, Y. P.; An, P. P.; Korneev, A. A.; Murphy, A.; Bezryadin, A.; Gol’tsman, G. N.
	Title	Quasi-1-dimensional superconductivity in highly disordered NbN nanowires			Type	Miscellaneous
	Year	2016	Publication	arXiv	Abbreviated Journal
	Volume		Issue		Pages
	Keywords	narrow NbN nanowires, BCS
	Abstract	The topic of superconductivity in strongly disordered materials has attracted a significant attention. In particular vivid debates are related to the subject of intrinsic spatial inhomogeneity responsible for non-BCS relation between the superconducting gap and the pairing potential. Here we report experimental study of electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. We find that conventional models based on phase slip concept provide reasonable fits for the shape of the R(T) transition curve. Temperature dependence of the critical current follows the text-book Ginzburg-Landau prediction for quasi-one-dimensional superconducting channel Ic~(1-T/Tc)^3/2. Hence, one may conclude that the intrinsic electronic inhomogeneity either does not exist in our structures, or, if exist, does not affect their resistive state properties.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes	Duplicated as 1332			Approved	no
	Call Number				Serial	1338
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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.
	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	1941-0069	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1681
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	Author	Gershenzon, E. M.; Gol’tsman, G. N.; Semenov, A. D.; Sergeev, A. V.
	Title	Mechanism of picosecond response of granular YBaCuO films to electromagnetic radiation			Type	Journal Article
	Year	1991	Publication	IEEE Trans. Magn.	Abbreviated Journal	IEEE Trans. Magn.
	Volume	27	Issue	2	Pages	1321-1324
	Keywords	YBCO HTS detectors
	Abstract	Ultrafast mechanisms of radiation detection in granular YBaCuO films are studied in the wide wavelength range from millimeter waves to near infrared. With an increase in radiation frequency, the Josephson detection at the grain-boundary weak links is replaced by electron heating into the grains. This change occurs in the submillimeter wavelength range. The electron-phonon relaxation time tau /sub eph/ is determined from direct measurements, quasi-stationary electron heating measurements, and the frequency dependence of the current at which maximum voltage shift is observed. The temperature dependence of tau /sub eph/ at T<or=40 K was found to be tau /sub eph/ approximately T/sup -1/. The results show that detectors with a response time of a few picoseconds at nitrogen temperature are attainable.
	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	1941-0069	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1679
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	Author	Gershenzon, E. M.; Gol’tsman, G. N.; Dzardanov, A. L.; Zorin, M. A.
	Title	Ultrafast superconductive switch			Type	Journal Article
	Year	1991	Publication	IEEE Trans. Magn.	Abbreviated Journal	IEEE Trans. Magn.
	Volume	27	Issue	2	Pages	2844-2846
	Keywords	Nb superconducting switch
	Abstract	The transition from superconductive to resistive state caused by infrared radiation and bias current pulses was investigated in order to minimize switching time tau and driving power W. Experimental results for Nb microstrips confirm the correctness of calculations based on the model of electron heating. For Nb switches, tau measured directly is 0.3-0.8 ns for radiation pulses and 1-3 ns for bias current pulses at T=4.2 K, while for YBaCuO switches at T=77 K it is expected to be several picoseconds. For an YBaCuO sample with the dimensions of 520.15 mu m/sup 2/, W was 10 mW, and it can be further reduced to the order of several microwatts by decreasing the volume of the sample.
	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	1941-0069	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1680
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	Author	Gerecht, E.; Musante, C. F.; Zhuang, Y.; Yngvesson, K. S.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
	Title	NbN hot electron bolometric mixerss—a new technology for low-noise THz receivers			Type	Journal Article
	Year	1999	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	47	Issue	12	Pages	2519-2527
	Keywords	NbN HEB mixers
	Abstract	New advances in hot electron bolometer (HEB) mixers have recently resulted in record-low receiver noise temperatures at terahertz frequencies. We have developed quasi-optically coupled NbN HEB mixers and measured noise temperatures up to 2.24 THz, as described in this paper. We project the anticipated future performance of such receivers to have even lower noise temperature and local-oscillator power requirement as well as wider gain and noise bandwidths. We introduce a proposal for integrated focal plane arrays of HEB mixers that will further increase the detection speed of terahertz systems.
	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	1557-9670	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1560
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	Author	Semenov, A. D.; Goghidze, I. G.; Gol’tsman, G. N.; Sergeev, A. V.; Aksaev, E. E.; Gershenzon, E. M.
	Title	Non-equilibrium quasiparticle response to radiation and bolometric effect in YBaCuO films			Type	Journal Article
	Year	1993	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	3	Issue	1	Pages	2132-2135
	Keywords	YBCO HTS HEB detectors
	Abstract	The voltage photoresponse of structured current biased YBCO films on different substrates to 20-ps laser pulses of 0.63- mu m and 1.54- mu m wavelengths and to continuously modulated radiation of 2-mm wavelength is measured to temperatures around T_c. Fast picosecond decay of the response to pulsed radiation is followed by slow exponential relaxation with a nanosecond characteristic time depending on the substrate material and film dimensions. The slow component does not depend on wavelength and is attributed to the bolometric effect, while the magnitude of the fast component associated with nonequilibrium response rises with wavelength. More than an order-of-magnitude increase of the nonequilibrium response is seen from near-infrared to millimeter-wave range. This dependence plausibly reflects the low efficiency of multiplication of photoexcited electrons in YBaCuO compared to conventional superconductors.
	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	1558-2515	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1659
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	Author	Nebosis, R. S.; Heusinger, M. A.; Schatz, W.; Renk, K. F.; Gol’tsman, G. N.; Karasik, B. S.; Semenov, A. D.; Gershenzon, E. M.
	Title	Ultrafast photoresponse of a structured YBa₂Cu₃O_7-δ thin film to ultrashort FIR laser pulses			Type	Journal Article
	Year	1993	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	3	Issue	1	Pages	2160-2162
	Keywords	YBCO HTS detectors
	Abstract	The authors have investigated the photoinduced voltage response of a current-carrying structured YBa₂Cu₃O_7-δ thin film to ultrashort far-infrared (FIR) laser pulses in the frequency range from 0.7 THz to 7 THz. The detector has shown an almost constant sensitivity of 1 mV/W and a noise equivalent power of less than 5*10/sup -7/ W/ square root Hz. The temperature dependence of the decay time of the detector signal was studied for temperatures around the transition temperature of the film ( approximately 80 K). For a detector temperature where dR/dT had its maximum, the authors observed bolometric signals with decay times of about 2 ns, and for lower temperatures they observed nonbolometric signals with decay times of approximately 120 ps; the duration of the nonbolometric signals was limited by the time resolution of the electronic registration equipment.
	Address
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	Publisher		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
	Notes				Approved	no
	Call Number				Serial	1658
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	Author	Gol’tsman, G.; Okunev, O.; Chulkova, G.; Lipatov, A.; Dzardanov, A.; Smirnov, K.; Semenov, A.; Voronov, B.; Williams, C.; Sobolewski, R.
	Title	Fabrication and properties of an ultrafast NbN hot-electron single-photon detector			Type	Journal Article
	Year	2001	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	11	Issue	1	Pages	574-577
	Keywords	NbN SSPD, SNSPD
	Abstract	A new type of ultra-high-speed single-photon counter for visible and near-infrared wavebands based on an ultrathin NbN hot-electron photodetector (HEP) has been developed. The detector consists of a very narrow superconducting stripe, biased close to its critical current. An incoming photon absorbed by the stripe produces a resistive hotspot and causes an increase in the film’s supercurrent density above the critical value, leading to temporary formation of a resistive barrier across the device and an easily measurable voltage pulse. Our NbN HEP is an ultrafast (estimated response time is 30 ps; registered time, due to apparatus limitations, is 150 ps), frequency unselective device with very large intrinsic gain and negligible dark counts. We have observed sequences of output pulses, interpreted as single-photon events for very weak laser beams with wavelengths ranging from 0.5 /spl mu/m to 2.1 /spl mu/m and the signal-to-noise ratio of about 30 dB.
	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	1558-2515	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1547
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	Author	Kawamura, J.; Tong, C.-Y. E.; Blundell, R.; Papa, D. C.; Hunter, T. R.; Patt, F.; Gol’tsman, G.; Gershenzon, E.
	Title	Terahertz-frequency waveguide NbN hot-electron bolometer mixer			Type	Journal Article
	Year	2001	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	11	Issue	1	Pages	952-954
	Keywords	NbN HEB mixers
	Abstract	We have developed a low-noise waveguide heterodyne receiver for operation near 1 THz using phonon-cooled NbN hot-electron bolometers. The mixer elements are submicron-sized microbridges of 4 nm-thick NbN film fabricated on a quartz substrate. Operating at a bath temperature of 4.2 K, the double-sideband receiver noise temperature is 760 K at 1.02 THz and 1100 K at 1.26 THz. The local oscillator is provided by solid-state sources, and power measured at the source is less than 1 /spl mu/W. The intermediate frequency bandwidth exceeds 2 GHz. The receiver was used to make the first ground-based heterodyne detection of a celestial spectroscopic line above 1 THz.
	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	1558-2515	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1546
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	Author	Chulkova, G.; Milostnaya, I.; Korneev, A.; Minaeva, O.; Rubtsova, I.; Voronov, B.; Okunev, O.; Smirnov, K.; Gol’tsman, G.; Kitaygorsky, J.; Cross, A.; Pearlman, A.; Sobolewski, R.; Slysz, W.
	Title	Superconducting nanostructures for counting of single photons in the infrared range			Type	Conference Article
	Year	2005	Publication	Proc. 2-nd CAOL	Abbreviated Journal	Proc. 2-nd CAOL
	Volume	2	Issue		Pages	100-103
	Keywords	SSPD, SNSPD
	Abstract	We present our studies on ultrafast superconducting single-photon detectors (SSPDs) based on ultrathin NbN nanostructures. Our SSPDs are patterned by electron beam lithography from 4-nm thick NbN film into meander-shaped strips covering square area of 10/spl times/10 /spl mu/m/sup 2/. The advances in the fabrication technology allowed us to produce highly uniform 100-120-nm-wide strips with meander filling factor close to 0.6. The detectors exploit a combined detection mechanism, where upon a single-photon absorption, an avalanche of excited hot electrons and the biasing supercurrent, jointly produce a picosecond voltage transient response across the superconducting nanostrip. The SSPDs are typically operated at 4.2 K, but they have shown that their sensitivity in the infrared radiation range can be significantly improved by lowering the operating temperature from 4.2 K to 2 K. When operated at 2 K, the SSPD quantum efficiency (QE) for visible light photons reaches 30-40%, which is the saturation value limited by optical absorption of our 4-nm-thick NbN film. For 1.55 /spl mu/m photons, QE was /spl sim/20% and decreases exponentially with the increase of the optical wavelength, but even at the wavelength of 6 /spl mu/m the detector remains sensitive to single photons and exhibits QE of about 10/sup -2/%. The dark (false) count rate at 2 K is as low as 2 /spl times/ 10/sup -4/ s/sup -1/, what makes our detector essentially a background-limited sensor. The very low dark-count rate results in the noise equivalent power (NEP) as low as 10/sup -18/ WHz/sup -1/2/ for the mid-infrared range (6 /spl mu/m). Further improvement of the SSPD performance in the mid-infrared range can be obtained by substituting NbN for the other, lower-T/sub c/ superconductors with the narrow superconducting gap and low quasiparticle diffusivity. The use of such materials will shift the cutoff wavelength towards the values even longer than 6 /spl mu/m.
	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		ISBN		Medium
	Area		Expedition		Conference	Second International Conference on Advanced Optoelectronics and Lasers
	Notes				Approved	no
	Call Number				Serial	1461
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	Author	Okunev, O.; Chulkova, G.; Milostnaya, I.; Antipov, A.; Smirnov, K.; Morozov, D.; Korneev, A.; Voronov, B.; Gol’tsman, G.; Stysz, W.; Wegrzecki, M.; Bar, J.; Grabiec, P.; Gorska, M.; Pearlman, A.; Cross, A.; Kitaygorsky, J.; Sobolewski, R.
	Title	Registration of infrared single photons by a two-channel receiver based on fiber-coupled superconducting single-photon detectors			Type	Conference Article
	Year	2005	Publication	Proc. 2-nd CAOL	Abbreviated Journal	Proc. 2-nd CAOL
	Volume	2	Issue		Pages	282-285
	Keywords	NbN SSPD, SNSPD
	Abstract	Single-photon detectors (SPDs) are the foundation of all quantum communications (QC) protocols. Among different classes of SPDs currently studied, NbN superconducting SPDs (SSPDs) are established as the best devices for ultrafast counting of single photons in the infrared (IR) wavelength range. The SSPDs are nanostructured, 100 /spl mu/m/sup 2/ in total area, superconducting meanders, patterned by electron lithography in ultra-thin NbN films. Their operation has been explained within a phenomenological hot-electron photoresponse model. We present the design and performance of a novel, two-channel SPD receiver, based on two fiber-coupled NbN SSPDs. The receivers have been developed for fiber-based QC systems, operational at 1.3 /spl mu/m and 1.55 /spl mu/m telecommunication wavelengths. They operate in the temperature range from 4.2 K to 2 K, in which the NbN SSPDs exhibit their best performance. The receiver unit has been designed as a cryostat insert, placed inside a standard liquid-helium storage dewar. The input of the receiver consists of a pair of single-mode optical fibers, equipped with the standard FC connectors and kept at room temperature. Coupling between the SSPD and the fiber is achieved using a specially designed, precise micromechanical holder that places the fiber directly on top of the SSPD nanostructure. Our receivers achieve the quantum efficiency of up to 7% for near-IR photons, with the coupling efficiency of about 30%. The response time was measured to be <300 ps and it was limited by our read-out electronics. The jitter of fiber-coupled SSPDs is <35 ps and their dark-count rate is below 1 s/sup -1/. The presented performance parameters show that our single-photon receivers are fully applicable for quantum-correlation-type QC systems, including practical quantum cryptography.
	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		ISBN		Medium
	Area		Expedition		Conference	Second International Conference on Advanced Optoelectronics and Lasers
	Notes				Approved	no
	Call Number				Serial	1462
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	Author	Xu, Y.; Zheng, X.; Williams, C.; Verevkin, A.; Sobolewski, R.; Chulkova, G.; Lipatov, A.; Okunev, O.; Smirnov, K.; Gol’tsman, G. N.
	Title	Ultrafast superconducting hot-electron single-photon detector			Type	Conference Article
	Year	2001	Publication	CLEO	Abbreviated Journal	CLEO
	Volume		Issue		Pages	345
	Keywords	NbN SSPD, SNSPD
	Abstract	Summary form only given. The current most-pressing need is to develop a practical, GHz-range counting single-photon detector, operational at either 1.3-/spl mu/m or 1.55-/spl mu/m radiation wavelength, for novel quantum communication and quantum cryptography systems. The presented solution of the problem is to use an ultrafast hot-electron photodetector, based on superconducting thin-film microstructures. This type of device is very promising, due to the macroscopic quantum nature of superconductors. Very fast response time and the small, (meV range) value of the superconducting energy gap characterize the superconductor, leading to the efficient avalanche process even for infrared photons.
	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		ISBN		Medium
	Area		Expedition		Conference	Technical Digest. Summaries of papers presented at the Conference on Lasers and Electro-Optics. Postconference Technical Digest (IEEE Cat. No.01CH37170)
	Notes				Approved	no
	Call Number				Serial	1545
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	Author	Rosfjord, K. M.; Yang, J. K. W.; Dauler, E. A.; Anant, V.; Berggren, K. K.; Kerman, A. J.; Voronov, B. M.; Gol’tsman, G. N.
	Title	Increased detection efficiencies of nanowire single-photon detectors by integration of an optical cavity and anti-reflection coating			Type	Conference Article
	Year	2006	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
	Volume		Issue		Pages	JTuF2 (1 to 2)
	Keywords	SSPD, SNSPD
	Abstract	We fabricate and test superconducting NbN-nanowire single-photon detectors with an integrated optical cavity and anti-reflection coating. We design the cavity and coating such as to maximize absorption in the NbN film of the detector.
	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		ISBN		Medium
	Area		Expedition		Conference	2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference
	Notes				Approved	no
	Call Number				Serial	1452
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	Author	Smirnov, K.; Korneev, A.; Minaeva, O.; Divochij, A.; Rubtsova, I.; Antipov, A.; Ryabchun, S.; Okunev, O.; Milostnaya, I.; Chulkova, G.; Voronov, B.; Kaurova, N.; Seleznev, V.; Korotetskaya, Y.; Gol’tsman, G.
	Title	Superconducting single-photon detector for near- and middle IR wavelength range			Type	Conference Article
	Year	2006	Publication	Proc. 16th Int. Crimean Microwave and Telecommunication Technology	Abbreviated Journal	Proc. 16th Int. Crimean Microwave and Telecommunication Technology
	Volume	2	Issue		Pages	684-685
	Keywords	NbN SSPD, SNSPD
	Abstract	Presented in this paper are the results of research of NbN-film superconducting single-photon detector. At 2 K temperature, quantum efficiency in the visible light (0.56 mum) reaches 30-40 %. With the wavelength increase quantum efficiency decreases and comes to 20% at 1.55 mum and 0.02% at 5.6 mum. Minimum dark counts rate is 2times10-4s-1. The jitter of detector is 35 ps. The detector was successfully implemented for integrated circuits non-invasive optical testing. It is also perspective for quantum cryptography systems
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	Russian	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1447
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	Author	Svechnikov, S. I.; Finkel, M. I.; Maslennikov, S. N.; Vachtomin, Y. B.; Smirnov, K. V.; Seleznev, V. A.; Korotetskaya, Y. P.; Kaurova, N. S.; Voronov, B. M.; Gol’tsman, G. N.
	Title	Superconducting hot electron bolometer mixer for middle IR range			Type	Conference Article
	Year	2006	Publication	Proc. 16th Int. Crimean Microwave and Telecommunication Technology	Abbreviated Journal	Proc. 16th Int. Crimean Microwave and Telecommunication Technology
	Volume	2	Issue		Pages	686-687
	Keywords	IR NbN HEB mixer, detector, GaAs substrate
	Abstract	The developed directly lens coupled hot electron bolometer (HEB) mixer was based on 5 nm superconducting NbN deposited on GaAs substrate. The layout of the structure, including 30x20 mcm^2 active area coupled with a 50 Ohm coplanar line, was patterned by photolithography. The responsivity of the mixer was measured in a direct detection mode in the 25-64 THz frequency range. The noise performance of the mixer and the directivity of the receiver were investigated in a heterodyne mode. A 10.6 mum wavelength CW CO2 laser was utilized as a local oscillator.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	4023440			Serial	1297
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	Author	Vachtomin, Y. B.; Antipov, S. V.; Maslennikov, S. N.; Smirnov, K. V.; Polyakov, S. L.; Zhang, W.; Svechnikov, S. I.; Kaurova, N. S.; Grishina, E. V.; Voronov, B. M.; Gol’tsman, G. N.
	Title	Quasioptical hot electron bolometer mixers based on thin NBN films for terahertz region			Type	Conference Article
	Year	2006	Publication	Proc. 16th Int. Crimean Microwave and Telecommunication Technology	Abbreviated Journal	Proc. 16th Int. Crimean Microwave and Telecommunication Technology
	Volume	2	Issue		Pages	688-689
	Keywords	NbN HEB mixers
	Abstract	Presented in this paper are the performances of HEB mixers based on 2-3.5 nm thick NbN films integrated with log-periodic spiral antenna. Double side-band receiver noise temperature values are 1300 K and 3100 K at 2.5 THz and at 3.8 THz, respectively. Mixer gain bandwidth is 5.2 GHz. Local oscillator power is 1-3 muW for mixers with different active area
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	Russian	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1445
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	Author	Ekstrom, H.; Karasik, B.; Weikle, R.; Yngvesson, K. S.; Gol’tsman, G.; Kollberg, E.; Gershenzon, E.
	Title	Mixers using superconducting Nb films in the resistive state			Type	Conference Article
	Year	1993	Publication	23rd European Microwave Conf.	Abbreviated Journal	23rd European Microwave Conf.
	Volume		Issue		Pages	787-789
	Keywords	Nb HEB mixers
	Abstract	The mixing of 20 GHz radiation in a Nb superconducting film in the resistive state was studied. The experiment gave evidence of electron-heating to be the origin of the non-linear phenomenon. The requirements on the operation mode and on the film parameters in order to obtain small conversion losses or even gain are determined. Our measurements indicate a conversion loss of about 6-8 dB. The hot-electron bolometer is considered to be very promising for use in heterodyne receivers in a wide frequency range from microwaves to terahertz frequencies.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1651
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	Author	Gol’tsman, G. N.
	Title	Terahertz technology in Russia			Type	Conference Article
	Year	1994	Publication	24th European Microwave Conf.	Abbreviated Journal	24th European Microwave Conf.
	Volume	1	Issue		Pages	113-121
	Keywords	BWO, HEB mixers
	Abstract	The presentation consider the parameters and operating peculiarities of unique microwave generators of the terahertz range which have been created in Russia – the backward wave oscillators – as well as certain devices based on these generators, such as high resolution. spectrometers and time-resolving spectrometers with picosecond temporal resolution. Most resent BWO-based studies are illustrated by a project devoted to superconductive hot-electron. bolometers which are of great independent value for the terahertz technology as high-sensitive picosecond detectors and low noise broad-band mixers.
	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		ISBN		Medium
	Area		Expedition		Conference	24th European Microwave Conference
	Notes				Approved	no
	Call Number				Serial	1635
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	Author	Merkel, H. F.; Yagoubov, P. A.; Kroug, M.; Khosropanah, P.; Kollberg, E. L.; Gol’tsman, G. N.; Gershenzon, E. M.
	Title	Noise temperature and absorbed LO power measurement methods for NbN phonon-cooled hot electron bolometric mixers at terahertz frequencies			Type	Conference Article
	Year	1998	Publication	Proc. 28th European Microwave Conf.	Abbreviated Journal	Proc. 28th European Microwave Conf.
	Volume	1	Issue		Pages	294-299
	Keywords	NbN HEB mixers
	Abstract	In this paper the absorbed LO power requirements and the noise performance of NbN based phonon-cooled hot electron bolometric (HEB) quasioptical mixers are investigated for RF frequencies in the 0.55-1.1 range The minimal measured DSB noise temperatures are about 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz and 1250 K at 1.1 THz. The increase in noise temperature at 1.1THz is attributed to water absorption. The absorbed LO power is measured using a calorimetric approach. The results are subsequently corrected for lattice heating. These values are compared to results of a novel one dimensional hot spot mixer models and to a more traditional isotherm method which tends to underestimate the absorbed LO power for small bias powers. Typically a LO power between 50nW and 100nW is needed to pump the device to the optimal operating point.
	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		ISBN		Medium
	Area		Expedition		Conference	28th European Microwave Conference
	Notes				Approved	no
	Call Number				Serial	1580
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	Author	Richter, H.; Semenov, A.; Hubers, H.-W.; Smirnov, K.; Gol’tsman, G.; Voronov, B.
	Title	Phonon cooled hot-electron bolometric mixer for 1-5 THz			Type	Conference Article
	Year	2004	Publication	Proc. 29th IRMMW / 12th THz	Abbreviated Journal	Proc. 29th IRMMW / 12th THz
	Volume		Issue		Pages	241-242
	Keywords	NbN HEB mixers
	Abstract	Heterodyne receivers for applications in astronomy and planetary research need quantum limited sensitivity. In instruments which are currently built for SOFIA and Herschel, superconducting hot electron bolometers (HEB) are used to achieve this goal at frequencies above 1.4 THz. In order to optimize the performance for this frequency of hot electron bolometer mixers with different in-plane dimensions and logarithmic-spiral feed antennas have been investigated. Their noise temperatures and beam patterns were measured. Above 3 THz the best performance was achieved with a superconducting bridge of 2.0/spl times/0.2 /spl mu/m/sup 2/ incorporated in a logarithmic spiral antenna. The DSB noise temperatures were 2700 K, 4700 and 6400 K at 3.1 THz, 4.3 THz and 5.2 THz, respectively. The results demonstrate that the NbN HEB is very well suited as a mixer for THz heterodyne receivers up to at least 5 THz.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1506
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	Author	Gol’tsman, G.; Korneev, A.; Tarkhov, M.; Seleznev, V.; Divochiy, A.; Minaeva, O.; Kaurova, N.; Voronov, B.; Okunev, O.; Chulkova, G.; Milostnaya, I.; Smirnov, K.
	Title	Middle-infrared ultrafast superconducting single photon detector			Type	Conference Article
	Year	2007	Publication	32nd IRMW / 15th ICTE	Abbreviated Journal	32nd IRMW / 15th ICTE
	Volume		Issue		Pages	115-116
	Keywords	SSPD, SNSPD
	Abstract	We present the results of the research on quantum efficiency of the ultrathin-film superconducting single-photon detectors (SSPD) in the wavelength rage from 1 mum to 5.7 mum. Reduction of operation temperature to 1.6 K allowed us to measure quantum efficiency of ~1 % at 5.7 mum wavelength with the SSPD made from 4-nm-thick NbN film. In a pursuit of further performance improvement we endeavored SSPD fabricating from 4-nm-thick MoRe film as an alternative material. The MoRe film exhibited transition temperature of 7.7K, critical current density at 4.2 K temperature was 1.1times10 6 A/cm 2 , and diffusivity 1.73 cmVs. The single-photon response was observed with MoRe SSPD at 1.3 mum wavelength with quantum efficiency estimated to be 0.04%.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1246
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	Author	Pentin, I. V.; Smirnov, A. V.; Ryabchun, S. A.; Gol’tsman, G. N.; Vaks, V. L.; Pripolzin, S. I.; Paveliev, D. G.
	Title	Heterodyne source of THz range based on semiconductor superlattice multiplier			Type	Conference Article
	Year	2011	Publication	IRMMW-THz	Abbreviated Journal	IRMMW-THz
	Volume		Issue		Pages	1-2
	Keywords	NbN HEB mixer, superlattice
	Abstract	We present the results of our studies of the possibility of developing a heterodyne receiver incorporating a hot-electron bolometer mixer as the detector and a semiconductor superlattice multiplier driven by a reference synthesizer as the local oscillator. We observe that such a local oscillator offers enough power in the terahertz range to pump the HEB into the operating state.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	6105209			Serial	1384
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	Author	Zhang, J.; Pearlman, A.; Slysz, W.; Verevkin, A.; Sobolewski, R.; Wilsher, K.; Lo, W.; Okunev, O.; Korneev, A.; Kouminov, P.; Chulkova, G.; Gol’tsman, G. N.
	Title	A superconducting single-photon detector for CMOS IC probing			Type	Conference Article
	Year	2003	Publication	Proc. 16-th LEOS	Abbreviated Journal	Proc. 16-th LEOS
	Volume	2	Issue		Pages	602-603
	Keywords	NbN SSPD, SNSPD
	Abstract	In this paper, a novel, time-resolved, NbN-based, superconducting single-photon detector (SSPD) has been developed for probing CMOS integrated circuits (ICs) using photon emission timing analysis (PETA).
	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		ISBN		Medium
	Area		Expedition		Conference	The 16th Annual Meeting of the IEEE Lasers and Electro-Optics Society, 2003. LEOS 2003.
	Notes				Approved	no
	Call Number				Serial	1510
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	Author	Maslennikov, S. N.; Morozov, D. V.; Ozhegov, R. V.; Smirnov, K. V.; Okunev, O. V.; Gol’tsman, G. N.
	Title	Imaging system for submillimeter wave range based on AlGaAs/GaAs hot electron bolometer mixers			Type	Conference Article
	Year	2004	Publication	Proc. 5-th MSMW	Abbreviated Journal	Proc. 5-th MSMW
	Volume	2	Issue		Pages	558-560
	Keywords	AlGaAs/GaAs HEB mixers
	Abstract	Electromagnetic radiation of the submillimeter (SMM) range is dispersed and absorbed significantly less than infrared (IR) radiation when passing through different objects. That is the reason for the development of an SMM imaging system. In this paper, we discuss the design of an SMM heterodyne imager, based on a matrix of AlGaAs/GaAs heterostructure hot electron bolometer mixers (HEB) with relatively high (about 77 K) operating temperature. The predicted double side band (DSB) noise temperature is about 1000 K and optimal local oscillator (LO) power is about 1 /spl mu/W for such mixers, which seems to be quite prospective for an SMM heterodyne imager.
	Address	Kharkov, Ukraine
	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		ISBN		Medium
	Area		Expedition		Conference	The Fifth International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter, and Submillimeter Waves (IEEE Cat. No.04EX828)
	Notes				Approved	no
	Call Number				Serial	1487
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	Author	Tong, C.-Y. E.; Meledin, D.; Loudkov, D.; Blundell, R.; Erickson, N.; Kawamura, J.; Mehdi, I.; Gol’tsman, G.
	Title	A 1.5 THz Hot-Electron Bolometer mixer operated by a planar diode based local oscillator			Type	Conference Article
	Year	2003	Publication	IEEE MTT-S Int. Microwave Symp. Digest	Abbreviated Journal	IEEE MTT-S Int. Microwave Symp. Digest
	Volume	2	Issue		Pages	751-754
	Keywords	waveguide NbN HEB mixers
	Abstract	We have developed a 1.5 THz superconducting NbN Hot-Electron Bolometer mixer. It is operated by an all-solid-state Local Oscillator comprising of a cascade of 4 planar doublers following an MMIC based W-band power amplifier. The threshold available pump power is estimated to be 1 /spl mu/W.
	Address	Philadelphia, PA, USA
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1516
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	Author	Gol’tsman, G. N.; Smirnov, K.; Kouminov, P.; Voronov, B.; Kaurova, N.; Drakinsky, V.; Zhang, J.; Verevkin, A.; Sobolewski, R.
	Title	Fabrication of nanostructured superconducting single-photon detectors			Type	Journal Article
	Year	2003	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	13	Issue	2	Pages	192-195
	Keywords	NbN SSPD, SNSPD
	Abstract	Fabrication of NbN superconducting single-photon detectors, based on the hotspot effect is presented. The hotspot formation arises in an ultrathin and submicrometer-width superconductor stripe and, together with the supercurrent redistribution, leads to the resistive detector response upon absorption of a photon. The detector has a meander structure to maximally increase its active area and reach the highest detection efficiency. Main processing steps, leading to efficient devices, sensitive in 0.4-5 /spl mu/m wavelength range, are presented. The impact of various processing steps on the performance and operational parameters of our detectors is discussed.
	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	1558-2515	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1515
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	Author	Loudkov, D.; Tong, C.-Y. E.; Blundell, R.; Kaurova, N.; Grishina, E.; Voronov, B.; Gol’tsman, G.
	Title	An investigation of the performance of the superconducting HEB mixer as a function of its RF embedding impedance			Type	Journal Article
	Year	2005	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	15	Issue	2	Pages	472-475
	Keywords	waveguide NbN HEB mixers
	Abstract	We have conducted an investigation of the optimal embedding impedance for a waveguide superconducting hot-electron bolometric (HEB) mixer. Three mixer chip designs for 800 GHz, offering nominal embedding resistances of 70 /spl Omega/, 35 /spl Omega/, and 15 /spl Omega/, have been developed. We used both High Frequency Structure Simulator (HFSS) software and scale model impedance measurements in the design process. We subsequently fabricated HEB mixers to these designs using 3-4 nm thick NbN thin film. Receiver noise temperature measurements and Fourier Transform Spectrometer (FTS) scans were performed to determine the optimal combination of embedding impedance and normal-state resistance for a 50 Ohm IF load impedance. A receiver noise temperature of 440 K was measured at a local oscillator frequency 850 GHz for a mixer with normal state resistance of 62 /spl Omega/ incorporated into a circuit offering a nominal embedding impedance of 70 /spl Omega/. We conclude from our data that, for low noise operation, the normal state resistance of the HEB mixer element should be close to the embedding impedance of the mixer mount.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	1439677			Serial	1464
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	Author	Korneev, A.; Matvienko, V.; Minaeva, O.; Milostnaya, I.; Rubtsova, I.; Chulkova, G.; Smirnov, K.; Voronov, V.; Gol’tsman, G.; Slysz, W.; Pearlman, A.; Verevkin, A.; Sobolewski, R.
	Title	Quantum efficiency and noise equivalent power of nanostructured, NbN, single-photon detectors in the wavelength range from visible to infrared			Type	Journal Article
	Year	2005	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	15	Issue	2	Pages	571-574
	Keywords	NbN SSPD, SNSPD, QE, NEP
	Abstract	We present our studies on the quantum efficiency (QE) and the noise equivalent power (NEP) of the latest-generation, nanostructured, superconducting, single-photon detectors (SSPDs) in the wavelength range from 0.5 to 5.6 /spl mu/m, operated at temperatures in the 2.0- to 4.2-K range. Our detectors are designed as 4-nm-thick and 100-nm-wide NbN meander-shaped stripes, patterned by electron-beam lithography and cover a 10/spl times/10-/spl mu/m/sup 2/ active area. The best-achieved QE at 2.0 K for 1.55-/spl mu/m photons is 17%, and QE for 1.3-/spl mu/m infrared photons reaches its saturation value of /spl sim/30%. The SSPD NEP at 2.0 K is as low as 5/spl times/10/sup -21/ W/Hz/sup -1/2/. Our nanostructured SSPDs, operated at 2.0 K, significantly outperform their semiconducting counterparts, and, together with their GHz counting rate and picosecond timing jitter, they are devices-of-choice for practical quantum key distribution systems and free-space (even interplanetary) quantum optical communications.
	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	1558-2515	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1467
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	Author	Pearlman, A.; Cross, A.; Slysz, W.; Zhang, J.; Verevkin, A.; Currie, M.; Korneev, A.; Kouminov, P.; Smirnov, K.; Voronov, B.; Gol’tsman, G.; Sobolewski, R.
	Title	Gigahertz counting rates of NbN single-photon detectors for quantum communications			Type	Journal Article
	Year	2005	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	15	Issue	2	Pages	579-582
	Keywords	NbN SSPD, SNSPD
	Abstract	We report on the GHz counting rate and jitter of our nanostructured superconducting single-photon detectors (SSPDs). The devices were patterned in 4-nm-thick and about 100-nm-wide NbN meander stripes and covered a 10-/spl mu/m/spl times/10-/spl mu/m area. We were able to count single photons at both the visible and infrared telecommunication wavelengths at rates of over 2 GHz with a timing jitter of below 18 ps. We also present the model for the origin of the SSPD switching dynamics and jitter, based on the time-delay effect in the phase-slip-center formation mechanism during the detector photoresponse process. With further improvements in our readout electronics, we expect that our SSPDs will reach counting rates of up to 10 GHz. An integrated quantum communications receiver based on two fiber-coupled SSPDs and operating at 1550-nm wavelength is also presented.
	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	1558-2515	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1465
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	Author	Yang, J. K. W.; Dauler, E.; Ferri, A.; Pearlman, A.; Verevkin, A.; Gol’tsman, G.; Voronov, B.; Sobolewski, R.; Keicher, W. E.; Berggren, K. K.
	Title	Fabrication development for nanowire GHz-counting-rate single-photon detectors			Type	Journal Article
	Year	2005	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	15	Issue	2	Pages	626-630
	Keywords	NbN SSPD, SNSPD
	Abstract	We have developed a fabrication process for GHz-counting-rate, single-photon, high-detection-efficiency, NbN, nanowire detectors. We have demonstrated two processes for the device patterning, one based on the standard polymethylmethacrylate (PMMA) organic positive-tone electron-beam resist, and the other based on the newer hydrogen silsesquioxane (HSQ) negative-tone spin-on-glass resist. The HSQ-based process is simple and robust, providing high resolution and the prospect of high fill-factors. Initial testing results show superconductivity in the films, and suggest that the devices exhibit photosensitivity.
	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	1558-2515	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1466
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	Author	Tong, C.-Y. E.; Trifonov, A.; Shurakov, A.; Blundell, R.; Gol’tsman, G.
	Title	A microwave-operated hot-electron-bolometric power detector for terahertz radiation			Type	Journal Article
	Year	2015	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
	Volume	25	Issue	3	Pages	2300604 (1 to 4)
	Keywords	NbN HEB mixer
	Abstract	A new class of microwave-operated THz power detectors based on the NbN hot-electron-bolometer (HEB) mixer is proposed. The injected microwave signal ( 1 GHz) serves the dual purpose of pumping the HEB element and enabling the read-out of the internal state of the device. A cryogenic amplifier amplifies the reflected microwave signal from the device and a homodyne scheme recovers the effects of the incident THz radiation. Two modes of operation have been identified, depending on the level of incident radiation. For weak signals, we use a chopper to chop the incident radiation against a black body reference and a lock-in amplifier to perform synchronous detection of the homodyne readout. The voltage measured is proportional to the incident power, and we estimate an optical noise equivalent power of 5pW/ √Hz at 0.83 THz. At higher signal levels, the homodyne circuit recovers the stream of steady relaxation oscillation pulses from the HEB device. The frequency of these pulses is in the MHz frequency range and bears a linear relationship with the incident THz radiation over an input power range of 15 dB. A digital frequency counter is used to measure THz power. The applicable power range is between 1 nW and 1 μW.
	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	1558-2515	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1354
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	Author	Blundell, R.; Kawamura, J. H.; Tong, C. E.; Papa, D. C.; Hunter, T. R.; Gol’tsman, G. N.; Cherednichenko, S. I.; Voronov, B. M.; Gershenzon, E. M.
	Title	A hot-electron bolometer mixer receiver for the 680-830 GHz frequency range			Type	Conference Article
	Year	1998	Publication	Proc. 6-th Int. Conf. Terahertz Electron.	Abbreviated Journal	Proc. 6-th Int. Conf. Terahertz Electron.
	Volume		Issue		Pages	18-20
	Keywords	NbN HEB mixers
	Abstract	We describe a heterodyne receiver designed to operate in the partially transparent atmospheric windows centered on 680 and 830 GHz. The receiver incorporates a niobium nitride thin film, cooled to 4.2 K, as the phonon-cooled hot-electron mixer element. The double sideband receiver noise, measured over the frequency range 680-830 GHz, is typically 700-1300 K. The instantaneous output bandwidth of the receiver is 600 MHz. This receiver has recently been used at the SubMillimeter Telescope, jointly operated by the Steward Observatory and the Max Planck Institute for Radioastronomy, for observations of the neutral carbon and CO spectral lines at 810 GHz and at 806 and 691 GHz respectively. Laboratory measurements on a second mixer in the same test receiver have yielded extended high frequency performance to 1 THz.
	Address	Leeds, UK
	Corporate Author				Thesis
	Publisher	IEEE	Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	0-7803-4903-2	Medium
	Area		Expedition		Conference	IEEE Sixth International Conference on Terahertz Electronics Proceedings. THZ 98. (Cat. No.98EX171)
	Notes				Approved	no
	Call Number				Serial	1581
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	Author	Yagoubov, P.; Kroug, M.; Merkel, H.; Kollberg, E.; Schubert, J.; Hubers, H.-W.; Schwaab, G.; Gol’tsman, G.; Gershenzon, E.
	Title	Performance of NbN phonon-cooled hot-electron bolometric mixer at Terahertz frequencies			Type	Conference Article
	Year	1998	Publication	Proc. 6-th Int. Conf. Terahertz Electron.	Abbreviated Journal	Proc. 6-th Int. Conf. Terahertz Electron.
	Volume		Issue		Pages	149-152
	Keywords	NbN HEB mixers
	Abstract	The performance of a NbN based phonon-cooled Hot Electron Bolometric (HEB) quasioptical mixer is investigated in the 0.65-3.12 THz frequency range. The device is made from a 3 nm thick NbN film on high resistivity Si and integrated with a planar spiral antenna on the same substrate. The in-plane dimensions of the bolometer strip are 0.2/spl times/2 /spl mu/m. The results of the DSB noire temperature are: 1300 K at 650 GHz, 4700 K at 2.5 TBz and 10000 K at 3.12 THz. The RF bandwidth of the receiver is at least 2.5 THz. The amount of LO power absorbed in the bolometer is about 100 nW. The mixer is linear to within 1 dB compression up to the signal level 10 dB below that of the LO. The intrinsic single sideband conversion gain is measured to be -9 dB, the total conversion gain -14 dB.
	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		ISBN		Medium
	Area		Expedition		Conference	IEEE Sixth International Conference on Terahertz Electronics Proceedings. THZ 98. (Cat. No.98EX171)
	Notes				Approved	no
	Call Number				Serial	1582
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	Author	Krause, S.; Mityashkin, V.; Antipov, S.; Gol’tsman, G.; Meledin, D.; Desmaris, V.; Belitsky, V.; Rudziński, M.
	Title	Reduction of phonon escape time for nbn hot electron bolometers by using gan buffer layers			Type	Journal Article
	Year	2017	Publication	IEEE Trans. Terahertz Sci. Technol.	Abbreviated Journal	IEEE Trans. Terahertz Sci. Technol.
	Volume	7	Issue	1	Pages	53-59
	Keywords	NbN HEB mixer
	Abstract	In this paper, we investigated the influence of the GaN buffer layer on the phonon escape time of phonon-cooled hot electron bolometers (HEBs) based on NbN material and compared our findings to conventionally employed Si substrate. The presented experimental setup and operation of the HEB close to the critical temperature of the NbN film allowed for the extraction of phonon escape time in a simplified manner. Two independent experiments were performed at GARD/Chalmers and MSPU on a similar experimental setup at frequencies of approximately 180 and 140 GHz, respectively, and have shown reproducible and consistent results. By fitting the normalized IF measurement data to the heat balance equations, the escape time as a fitting parameter has been deduced and amounts to 45 ps for the HEB based on Si substrate as in contrast to a significantly reduced escape time of 18 ps for the HEB utilizing the GaN buffer layer under the assumption that no additional electron diffusion has taken place. This study indicates a high phonon transmissivity of the NbN-to-GaN interface and a prospective increase of IF bandwidth for HEB made of NbN on GaN buffer layers, which is desirable for future THz HEB heterodyne receivers.
	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	2156-3446	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1330
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	Author	Karasik, B.S.; Lindgren, M.; Zorin, M.A.; Danerud, M.; Winkler, D.; Trifonov, V.V.; Gol’tsman, G.N.; Gershenzon, E.M.
	Title	Picosecond detection and broadband mixing of near-infrared radiation by YBaCuO films			Type	Conference Article
	Year	1994	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	2159	Issue		Pages	68-76
	Keywords	YBCO HTS HEB mixer
	Abstract	Nonequilibrium picosecond and bolometric responses of YBCO films 500 angstroms thick patterned into 20 X 20 micrometers ² size structure to 17 ps laser pulses and modulated radiation of GaAs and CO₂ lasers have been studied. The modulation frequencies up to 10 GHz for GaAs laser and up to 1 GHz for CO₂ were attained. The use of small radiation power (1 – 10 mW/cm² for cw radiation and 10 – 100 nJ/cm² for pulse radiation) in combination with high sensitive read-out system made possible to avoid any non-linear transient processes caused by an overheating of sample above a critical temperature or S-N switching enhanced by an intense radiation. Responses due to the change of kinetic inductance were believed to be negligible. The only signals observed were caused by a small change of the film resistance either in the resistive state created by a bias current or in the normal state. The data obtained by means of pulse and modulation techniques are in agreement. The responsivity about 1 V/W was measured at 1 GHz modulation frequency both for 0.85 micrometers and 10.6 micrometers wavelengths. The sensitivity of high-T_c fast wideband infrared detector is discussed.
	Address
	Corporate Author				Thesis
	Publisher	Spie	Place of Publication		Editor	Nahum, M.; Villegier, J.-C.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	High-Temperature Superconducting Detectors: Bolometric and Nonbolometric
	Notes				Approved	no
	Call Number				Serial	1640
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	Author	Gol’tsman, G. N.; Kouminov, P. B.; Goghidze, I. G.; Karasik, B. S.; Gershenzon, E. M.
	Title	Nonbolometric and fast bolometric responses of YBaCuO thin films in superconducting, resistive, and normal states			Type	Conference Article
	Year	1994	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	2159	Issue		Pages	81-86
	Keywords	YBCO HTS HEB, nonbolornetric
	Abstract	The transient voltage response in both epitaxial and granular YBaCuO thin films to 20 ps pulses of YAG:Nd laser radiation with 0.63 micrometers and 1.54 micrometers was studied. In normal and resistive states both types of films demonstrate two components: nonequilibrium picosecond component and following bolometric nanosecond. The normalized amplitudes are almost the same for all films. In superconducting state we observed a kinetic inductive response and two-component shape after integration. The normalized amplitude of the response in granular films is up to several orders of magnitude larger than in epitaxial films. We interpret the nonequilibrium response in terms of a suppression of order parameter by the excess of quasiparticles followed by the change of resistance in normal and resistive states or kinetic inductance in superconducting state. The sharp rise of inductive response in granular films is explained both by a diminishing of the crossection for current percolation through the disordered network os Josephson weak links and by a decrease of condensate density in neighboring regions.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Nahum, M.; Villegier, J.-C.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	High-Temperature Superconducting Detectors: Bolometric and Nonbolometric
	Notes				Approved	no
	Call Number				Serial	1641
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	Author	Karasik, B. S.; Zorin, M. A.; Milostnaya, I. I.; Elantev, A. I.; Gol’tsman, G. N.; Gershenzon, E. M.
	Title	Evidence of subnanosecond transition stage in S-N current switching of YBaCuO films			Type	Conference Article
	Year	1994	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	2160	Issue		Pages	74-82
	Keywords	YBCO HTS switches
	Abstract	We report on a study of S-N and N-S current switching in high quality YBaCuO films deposited onto ZrO₂ and NdGaO₃ substrates. The films 60-120 nm thick prepared by laser ablation were structured into single strips and were provided with gold contacts. We monitored the time dependence of the resistance upon application of the voltage step on the film. Experiment performed within certain ranges of voltage amplitudes and temperatures showed the occurrence of the fast stage both in S-N (shorter than 300 ps) and N-S transition. We discuss the mechanism of switching taking into account the hot electron phenomena in YBaCuO. The contributions of various thermal processes in the subsequent stage of the resistance dynamic are also discussed. The basic limiting characteristics (average dissipated power, minimum work done for switching, maximum repetition rate) of a picosecond switch which is proposed to be developed are estimated.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Buhrman, R.A.; Clarke, J.T.; Daly, K.; Koch, R.H.; Luine, J.A.; Simon, R.W.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Superconductive Devices and Circuits
	Notes				Approved	no
	Call Number				Serial	1638
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	Author	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.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Armitage, J. C.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	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	Gol’tsman, G. N.; Gershenzon, E. M.
	Title	High speed hot-electron superconducting bolometer			Type	Conference Article
	Year	1993	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	2104	Issue		Pages	181-182
	Keywords	NbN HEb, Nb, Al
	Abstract	Physical limitation of response time of a superconducting bolometer as well as the nature of non-equilibrium detection of radiation have been investigated for Al, Nb and NbN thin films in spectral range from submillimeter to near-infraredwavelengths [1,2]. In the case of ideal heat removal from the film with the f_‘. 100A thickness the detection mechanism is an electron heating effect that is not selective to radiation wavelength in a very broad range. The response time ofan electron heating bolometer is determined by an electron-phonon interaction time. This time is of about 10 ns, 0.5 ns and 20 ps for Al, Nb, and NbN correspondingly near the critical temperature of the superconducting film. Thesensitive area of the bolometer consists of a number of narrow strips (with awidth of 1Ã‚Âµm) connected in parallel to contact pads; these pads together witha sapphire substrate and a ground plate represent the microstrip transmissionline with an impedance of 50 Q.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Birch, J.R.; Parker, T.J.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	18th International Conference on Infrared and Millimeter Waves
	Notes				Approved	no
	Call Number				Serial	1652
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	Author	Schwaab, G.W.; Auen, K.; Bruendermann, E.; Feinaeugle, R.; Gol’tsman, G.N.; Huebers, H.-W.; Krabbe, A.; Roeser, H.-P.; Sirmain, G.
	Title	2- to 6-THz heterodyne receiver array for the Stratospheric Observatory for Infrared Astronomy (SOFIA)			Type	Conference Article
	Year	1998	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	3357	Issue		Pages	85-96
	Keywords	NbN HEB mixers, applications, stratospheric observatory, airborne
	Abstract	The Institute of Space Sensor Technology of the German Aerospace Center (DLR) is developing a heterodyne array receiver for the frequency range 2 to 6 THz for the Stratospheric Observatory for Infrared Astronomy (SOFIA). Key science issues in that frequency range are the observation of lines of atoms [e.g. (OI)], ions [e.g. (CII), (NII)], and molecules (e.g. OH, HD, CO) with high spectral resolution to study the dynamics and evolution of galactic and extragalactic objects. Long term goal is the development of an integrated array heterodyne receiver with superconducting hot electron bolometric (HEB) mixers and p-type Ge or Si lasers as local oscillators. The first generation receiver will be composed of HEB mixers in a 2 pixel 2 polarization array which will be pumped by a gas laser local oscillator. Improved Schottky diode mixers are the backup solution for the HEBs. The state of the art of HEB mixer and p-type Ge laser technology are described as well as possible improvements in the ’conventional’ optically pumped far-infrared laser and Schottky diode mixer technology. Finally, the frequency coverage of the first generation heterodyne receiver for some important astronomical transitions is discussed. The expected sensitivity is compared to line fluxes measured by the ISO satellite.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Phillips, T.G.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Advanced Technology MMW, Radio, and Terahertz Telescopes
	Notes				Approved	no
	Call Number				Serial	1583
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	Author	Huebers, H.-W.; Schubert, J.; Semenov, A.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Schwaab, G. W.
	Title	NbN phonon-cooled hot-electron bolometer as a mixer for THz heterodyne receivers			Type	Conference Article
	Year	1999	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	3828	Issue		Pages	410-416
	Keywords	NbN HEB mixers
	Abstract	We have investigated a phonon-cooled NbN hot electron bolometric (HEB) mixer in the frequency range from 0.7 THz to 5.2 THz. The device was a 3.5 nm thin film with an in- plane dimension of 1.7 X 0.2 micrometers ² integrated in a complementary logarithmic spiral antenna. The measured DSB receiver noise temperatures are 1500 K, 2200 K, 2600 K, 2900 K, 4000 K, 5600 K and 8800 K. The sensitivity fluctuation, the long term stability, and the antenna pattern were measured and the suitability of the mixer for a practical heterodyne receiver is discussed.
	Address
	Corporate Author				Thesis
	Publisher	Spie	Place of Publication		Editor	Chamberlain, J.M.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Terahertz Spectroscopy and Applications II
	Notes				Approved	no
	Call Number				Serial	1477
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