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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 waveguide superconducting HEB mixer at different RF embedding impedances			Type	Conference Article
	Year	2005	Publication	Proc. 16^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 16^th Int. Symp. Space Terahertz Technol.
	Volume		Issue		Pages	226-229
	Keywords	waveguide NbN HEB mixers
	Abstract	We have conducted an investigation of the performance of superconducting hot-electron bolometric (HEB) mixer at 800 GHz as a function of the embedding impedance of the waveguide embedding circuit. Using a single half-height mixer block, we have developed three different mixer chip configurations, offering nominal embedding resistances of 70, 35, and 15 Ohms. Both the High Frequency Structure Simulator (HFSS) software and scaled model impedance measurements were employed in the design process. Two batches of HEB mixers were fabricated to these designs using 3-4 nm thick NbN thin film. The mixers were characterized through receiver noise temperature measurements and Fourier Transform Spectrometer (FTS) scans. Briefly, a minimum receiver noise temperature of 440 K was measured at a local oscillator frequency 850 GHz for a mixer of normal state resistance 62 Ohms incorporated into a circuit offering a nominal embedding impedance of 70 Ohms. We conclude from our data that, for low noise operation, the normal state resistance of the HEB mixer element should be close to that of 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				Serial	1472
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	Author	Cherednichenko, S.; Drakinskiy, V.; Baubert, J.; Lecomte, B.; Dauplay, F.; Krieg, J.-M.; Delorme, Y.; Feret, A.; Hübers, H.-W.; Semenov, A. D.; Gol’tsman, G. N.
	Title	2.5 THz multipixel heterodyne receiver based on NbN HEB mixers			Type	Abstract
	Year	2007	Publication	Proc. 18^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 18^th Int. Symp. Space Terahertz Technol.
	Volume		Issue		Pages	112
	Keywords	NbN HEB mixers
	Abstract	A 16 pixel heterodyne receiver for 2.5 THz has been developed based on NbN superconducting hot-electron bolometer (HEB) mixers. The receiver uses a quasioptical RF coupling approach where HEB mixers are integrated into double dipole antennas on 1.5μm thick Si3N4 / SiO2 membranes. Spherical mirrors (one per pixel) and backshort distance from the antenna have been used to design the output mixer beam profile. The camera design allows all 16 pixel IF readout in parallel. Measurements of the mixers sensitivity and the input RF band are presented, and compared against calculations.
	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	1419
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	Author	Semenov, A.; Richter, H.; Smirnov, A.; Günther, B.; Hübers, H.-W.; Il’in, K.; Siegel, M.; Gol’tsman, G.; Drakinskiy, V.; Merkel, H.; Karamarkovic, J.
	Title	Development of HEB mixers for GREAT and for security screening			Type	Abstract
	Year	2007	Publication	Proc. 18^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 18^th Int. Symp. Space Terahertz Technol.
	Volume		Issue		Pages	184
	Keywords	NbN HEB mixers, GREAT
	Abstract	We report the study on the quasioptical coupling efficiency and the gain bandwidth of NbN hot-electron bolometer mixers developed for the 4.7 THz channel of the German receiver for Astronomy at THz-frequencies (GREAT) and for security screening at subterahertz frequencies. Radiation coupling efficiency and directive properties of integrated lens antennas with log-spiral, log-periodic and double-slot planar feeds coupled to a hot-electron bolometer were experimentally studied at frequencies from 1 THz to 6 THz and compared with simulations based on the method of moments and the physical-optics ray tracing. For all studied antennas the modeled spectral dependence of the coupling efficiency fits to the experimental data obtained with both Fourier transform spectroscopy and noise temperature measurements only if the complex impedance of the bolometer is explicitly taken into account. Our experimental data did not indicate any noticeable contribution of the quantum noise to the system noise temperature. The experimentally observed deviation of the beam pattern from the model prediction increases with frequency and is most likely due to a non- ideality of the presently used lenses. Study of the intermediate frequency mixer gain at local oscillator (LO) frequencies between 2.5 THz and 0.3 THz showed an increase of the gain bandwidth at low LO frequencies that was understood as the contribution of the direct interaction of magnetic vortices with the radiation field. We have found that the non- homogeneous hot-spot model more adequately describes variation of the intermediate frequency bandwidth with the applied local oscillator power than any of uniform mixer models. The state-of-the-day performance of the GREAT 4.7-THz channel and the 0.8-THz security scanner will be 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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1420
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	Author	Gol’tsman, G. N.
	Title	The “Millimetron” project, a future space telescope mission			Type	Abstract
	Year	2007	Publication	Proc. 18^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 18^th Int. Symp. Space Terahertz Technol.
	Volume		Issue		Pages	255
	Keywords	Millimetron space observatory, VLBI
	Abstract	The goal of the Millimetron project is to develop a space observatory operating in the millimeter, sub-millimeter and infrared wavelength ranges using a 12-m actively cooled telescope in a single-dish mode and as an interferometer with the space-ground and space-space baselines (the later after the launch of the second identical space telescope). The Millimetron’s main reflector and other optics will be cooled down to 4K thus enabling astronomical observations with super high sensitivity in MM and subMM (down to nanoJansky level). Heterodyne observations in an interferometer mode at frequencies 0.1-1 THz will provide super high angular resolution. The main instruments, planned to be installed are wide-range imaging arrays, radiometers with spectrometers and polarimeters, VLBI heterodyne receivers, and Mikelson type interferometer devices. Wide-range MM and subMM imaging arrays and spectrometers will be based on a superconducting hot electron direct detectors with Andreev mirrors operating at 0.1 K. Such detectors are the best candidates to reach the noise equivalent power level of 10 -19 -10 -20 W/√Hz. Heterodyne receivers will be both SIS based superconducting integrated receiver with flux-flow oscillator as LO (0.1-0.9 THz range) and HEB based receivers using multiplied Gunn oscillator as LO for 1-2 THz range and quantum cascade lasers as LO for 2-5 THz range. For observations in middle IR region there will be installed large arrays of superconducting single photon detectors, providing imaging with very high dynamic range and ultimate 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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1422
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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.
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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		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	Ozhegov, R. V.; Gorshkov, K. N.; Smirnov, K. V.; Gol’tsman, G. N.; Filippenko, L. V.; Koshelets, V. P.
	Title	Terahertz imaging system based on superconducting integrated receiver			Type	Conference Article
	Year	2010	Publication	Proc. 2-nd Int. Conf. Terahertz and Microwave radiation: Generation, Detection and Applications	Abbreviated Journal	Proc. 2-nd Int. Conf. Terahertz and Microwave radiation: Generation, Detection and Applications
	Volume		Issue		Pages	20-22
	Keywords	SIS mixer, SIR
	Abstract	The development of terahertz imaging instruments for security systems is on the cutting edge of terahertz technology. We are developing a THz imaging system based on a superconducting integrated receiver (SIR). An SIR is a new type of heterodyne receiver based on an SIS mixer integrated with a flux-flow oscillator (FFO) and a harmonic mixer which is used for phase-locking the FFO. Developing an array of SIRs would allow obtaining amplitude and phase characteristics of incident radiation in the plane of the receiver. Employing an SIR in an imaging system means building an entirely new instrument with many advantages compare to traditional systems: i) high temperature resolution, comparable to the best results for incoherent receivers; ii) high spectral resolution allowing spectral analysis of various substances; iii) the local oscillator frequency can be varied to obtain images at different frequencies, effectively providing “color” images; iv) since a heterodyne receiver preserves the phase of the radiation, it is possible to construct 3D images. The paper presents a prototype THz imaging system using an 1 pixel SIR. We have studied the dependence of the noise equivalent temperature difference (NETD) on the integration time and also possible ways of achieving best possible sensitivity. An NETD of 13 mK was obtained with an integration time of 1 sec a detection bandwidth of 4 GHz at a local oscillator frequency of 520 GHz. An important advantage of an FFO is its wide operation range: 300-700 GHz.
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	Language		Summary Language		Original Title
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	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	ozhegov2010terahertz			Serial	1397
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	Author	Semenov, A.; Richter, H.; Hübers, H.-W.; Petrenko, D.; Tretyakov, I.; Ryabchun, S.; Finkel, M.; Kaurova, N.; Gol’tsman, G.; Risacher, C.; Ricken, O.; Güsten, R.
	Title	Optimization of the intermediate frequency bandwidth in the THz HEB mixers			Type	Abstract
	Year	2014	Publication	Proc. 25^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 25^th Int. Symp. Space Terahertz Technol.
	Volume		Issue		Pages	54
	Keywords	NbN HEB mixer
	Abstract	We report on the studies of the intermediate frequency (IF) bandwidth of quasi-optically coupled NbN hot-electron bolometer (HEB) mixers which are aimed at the optimization of the mixer performance at terahertz frequencies. Extension of the IF bandwidth due to the contribution of electron diffusion to the heat removal from NbN microbolometers has been already demonstrated for NbN HEBs at subterahertz frequencies. However, reducing the size of the microbolometer causes degradation of the noise temperature. Using in-situ multilayer manufacturing process we succeeded to improve the transparency of the contacts for electrons which go away from microbolometer to the metallic antenna. The improved transparency and hence coupling efficiency counterbalances the noise temperature degradation. HEB mixers were tested in a laboratory heterodyne receiver with a narrow-band cold filter which allowed us to eliminate direct detection. We used a local oscillator with a quantum cascade laser (QCL) at a frequency of 4.745 THz [1] which was developed for the H-Channel of the German Receiver for Astronomy at Terahertz frequencies (GREAT). Both the noise and gain bandwidth were measured in the IF range from 0.5 to 8 GHz using the hot-cold technique and preliminary calibrated IF analyzer with a tunable microwave filter. For optimized HEB geometry we found the noise bandwidth as large as 7 GHz. We compare our results with the conventional and the hot-spot mixer models and show that further extension of the IF bandwidth should be possible via improving the sharpness of the superconducting transition. The cross characterization of the HEB mixer was performed in the test bed of GREAT at the Max-Planck-Institut für Radioastronomie with the same QCL LO and delivered results which were consistent with the laboratory studies.
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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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1359
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	Author	Kinev, N. V.; Filippenko, L. V.; Ozhegov, R. V.; Gorshkov, K. N.; Gol’tsman, G. N.; Koshelets, V. P.
	Title	Superconducting integrated receiver with HEB-mixer			Type	Abstract
	Year	2014	Publication	Proc. 25^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 25^th Int. Symp. Space Terahertz Technol.
	Volume		Issue		Pages	78
	Keywords	NbN HEB mixer, SIR, superconducting integrated receiver
	Abstract	Detectors in THz range with high sensitivity are very essential nowadays in different fields: space technology, atmospheric research, medicine and security. The most sensitive heterodyne detectors below 1 THz are the SIS- mixers due to its extremely high non-linearity and low noise level. Nevertheless, their effective range is strongly limited by superconducting gap Δ (about 1 THz for NbN circuits). Above 1 THz the detectors based on HEB (hot electron bolometers) are more effective [1]; their operation frequency is not limited from above and can be up to 70 THz [2]. HEBs can perform as both direct and heterodyne detectors (mixers). All HEB-mixers are used with external heterodyne, most useful are synthesizer with multipliers, quantum cascade lasers or far infrared lasers and backward-wave oscillators. Superconducting integrated receiver (SIR) is based on implementation of both SIS-miser and flux flow oscillator (FFO) acting as heterodyne at single chip [3]. Such receiver has been successfully applied at TELIS balloon-borne instrument for study of atmospheric constituents [4] and looks as very promising device for other THz missions including space research. Thus, there is a task to expand its operating range to higher frequencies. The frequency range of the SIR the operation is limited by both the SIS-mixer and the FFO maximum frequencies. The idea of present work is implementation of the HEB as a mixer in the SIR instead of the SIS traditionally used. We introduce the first results of integrating the HEB-mixer coupled to planar slot antenna with the FFO on one chip. For properly FFO operation the SIS harmonic mixer is used to phase lock the oscillator. The scheme of the SIR based on the HEB- mixer is presented in fig. 1. We have demonstrated the principal possibility of integration of both the HEB-mixer and the flux-flow oscillator on a single chip and succeed with sufficient power coupling for properly receiver operation. We measured the direct response of the HEB coupled to the antenna at THz frequencies by the FTS setup and noise temperature of the receiver with standard Y- factor measuring technique. The SIR operating range 450-620 GHz was achieved with the best uncorrected noise temperature of about 1000 К. One should note that it is still quite low frequencies for effective operation of the HEB-mixer; therefore we expect to obtain the better results for frequencies above 700 GHz (up to 1.2 THz). Another additional task is to increase the FFO frequencies by using NbTiN electrodes instead of NbN; currently we are working on this issue. This work was supported by the RFBR grant, the Ministry of Education and Science of Russia and Russian Academy of Sciences. References 1. D. Semenov, H.-W. Hubers, J. Schubert, G. N. Gol’tsman, A. I. Elantiev, B. M. Voronov, E. M. Gershenzon, Design and performance of the lattice-cooled hot-electron terahertz mixer, J. Appl. Phys. 88, 6758, 2000. 2. Maslennikov S. N., Finkel M. I., Antipov S. V. et al. Spiral antenna coupled and directly coupled NbN HEB mixers in the frequency range from 1 to 70THz. Proc. 17 th international symposium on space terahertz technology. Paris, France: 2006.—may. Pp. 177 – 179. 3. V.P. Koshelets, S.V. Shitov. Integrated Superconducting Receivers. Supercond. Sci. Technol. Vol. 13. P. R53-R59. 2000. 4. Gert de Lange, Dick Boersma, Johannes Dercksen et.al. Development and Characterization of the Superconducting Integrated Receiver Channel of the TELIS Atmospheric Sounder. Supercond. Sci. Technol. vol. 23, No 4, 045016 (8pp). 2010.
	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	1363
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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	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	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	Yagoubov, P.; Hübers, H.-W.; Gol’tsman, G.; Semenov, A.; Gao, J.; Hoogeveen, R.; de Graauw, T.; Birk, M.; Selig, A.; de Korte, P.
	Title	Hot-electron bolometer mixers – technology for far-infrared heterodyne instruments in future atmospheric chemistry missions			Type	Conference Article
	Year	2001	Publication	Proc. 3rd Int. Symp. Submillimeter Wave Earth Observation From Space	Abbreviated Journal	Proc. 3rd Int. Symp. Submillimeter Wave Earth Observation From Space
	Volume		Issue		Pages	57-69
	Keywords	HEB mixers
	Abstract
	Address	Delmenhorst
	Corporate Author				Thesis
	Publisher	Logos-Verlag	Place of Publication		Editor	Buehler, S.; Berlin
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	3-89722-700-2	Medium
	Area		Expedition		Conference	International Symposium on Submillimeter Wave Earth Observation from Space, ISSMWEOS01
	Notes				Approved	no
	Call Number				Serial	1549
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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	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	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	Semenov, A. D.; Hübers, H.-W.; Gol’tsman, G. N.; Smirnov, K.
	Title	Superconducting quantum detector for astronomy and X-ray spectroscopy			Type	Conference Article
	Year	2002	Publication	Proc. Int. Workshop on Supercond. Nano-Electronics Devices	Abbreviated Journal	Proc. Int. Workshop on Supercond. Nano-Electronics Devices
	Volume		Issue		Pages	201-210
	Keywords	NbN SSPD, SNSPD, SQD, superconducting quantum detectors, X-ray spectroscopy
	Abstract	We propose the novel concept of ultra-sensitive energy-dispersive superconducting quantum detectors prospective for applications in astronomy and X-ray spectroscopy. Depending on the superconducting material and operation conditions, such detector may allow realizing background limited noise equivalent power 10−21 W Hz−1/2 in the terahertz range when exposed to 4-K background radiation or counting of 6-keV photon with almost 10—4 energy resolution. Planar layout and relatively simple technology favor integration of elementary detectors into a detector array.
	Address	Naples, Italy
	Corporate Author				Thesis
	Publisher	Springer	Place of Publication	Boston, MA	Editor	Pekola, J.; Ruggiero, B.; Silvestrini, P.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	978-1-4615-0737-6	Medium
	Area		Expedition		Conference	International Workshop on Superconducting Nano-Electronics Devices, May 28-June 1, 2001
	Notes				Approved	no
	Call Number	semenov2002superconducting			Serial	1525
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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	Smirnov, K. V.; Vakhtomin, Yu. B.; Divochiy, A. V.; Ozhegov, R. V.; Pentin, I. V.; Slivinskaya, E. V.; Tarkhov, M. A.; Gol’tsman, G. N.
	Title	Single-photon detectors for the visible and infrared parts of the spectrum based on NbN nanostructures			Type	Abstract
	Year	2009	Publication	Proc. Progress In Electromagnetics Research Symp.	Abbreviated Journal	Proc. Progress In Electromagnetics Research Symp.
	Volume		Issue		Pages	863-864
	Keywords	SSPD, SNSPD
	Abstract	The research by the group of Moscow State Pedagogical University into the hot-electron phenomena in thin superconducting films has led to the development of new types ofdetectors [1, 2] and their use both in fundamental and applied studies [3–6]. In this paper, wepresent the results of the development and fabrication of receiving systems for the visible andinfrared parts of the spectrum optimised for use in telecommunication systems and quantumcryptography.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Moscow, Russia	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	RPLAB @ sasha @ smirnovsession			Serial	1050
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	Author	Huebers, H.-W.; Semenov, A.; Richter, H.; Birk, M.; Krocka, M.; Mair, U.; Smirnov, K.; Gol’tsman, G. N.; Voronov, B. M.
	Title	Superconducting hot electron bolometer as mixer for far-infrared heterodyne receivers			Type	Conference Article
	Year	2003	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	4855	Issue		Pages	395-401
	Keywords	NbN HEB mixers
	Abstract	Heterodyne receivers for applications in astronomy need quantum limited sensitivity. In instruments which are currently under development for SOFIA or Herschel superconducting hot electron bolometers (HEB) will be used to achieve this goal at frequencies above 1.4 THz. We present results of the development of a phonon-cooled NbN HEB mixer for GREAT, the German Receiver for Astronomy at Terahertz Frequencies, which will be flown aboard SOFIA. The mixer is a small superconducting bridge incorporated in a planar feed antenna and a hyperhemispherical lens. Mixers with logarithmic-spiral and double-slot feed antennas have been investigated with respect to their noise temperature, conversion loss, linearity and beam pattern. At 2.5 THz a double sideband noise temperature of 2200 K was achieved. The conversion loss was 17 dB. The response of the mixer was linear up to 400 K load temperature. The performance was verified by measuring an emission line of methanol at 2.5 THz. The measured linewidth is in good agreement with the linewidth deduced from pressure broadening measurements at millimeter wavelength. The results demonstrate that the NbN HEB is very well suited as a mixer for far-infrared heterodyne receivers.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication	Tucson, USA	Editor	Phillips, T. G.; Zmuidzinas, J.
	Language		Summary Language		Original Title
	Series Editor		Series Title	Presented at the Society of Photo-Optical Instrumentation Engineers (SPIE) Conference	Abbreviated Series Title
	Series Volume	4855	Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Millimeter and Submillimeter Detectors for Astronomy
	Notes				Approved	no
	Call Number				Serial	335
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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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	Author	Korneev, A.; Minaeva, O.; Divochiy, A.; Antipov, A.; Kaurova, N.; Seleznev, V.; Voronov, B.; Gol’tsman, G.; Pan, D.; Kitaygorsky, J.; Slysz, W.; Sobolewski, R.
	Title	Ultrafast and high quantum efficiency large-area superconducting single-photon detectors			Type	Conference Article
	Year	2007	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	6583	Issue		Pages	65830I (1 to 9)
	Keywords	SSPD, SNSPD, superconducting NbN films, infrared single-photon detectors
	Abstract	We present our latest generation of superconducting single-photon detectors (SSPDs) patterned from 4-nm-thick NbN films, as meander-shaped 0.5-mm-long and 100-nm-wide stripes. The SSPDs exhibit excellent performance parameters in the visible-to-near-infrared radiation wavelengths: quantum efficiency (QE) of our best devices approaches a saturation level of 30% even at 4.2 K (limited by the NbN film optical absorption) and dark counts as low as 2x10^-4 Hz. The presented SSPDs were designed to maintain the QE of large-active-area devices, but, unless our earlier SSPDs, hampered by a significant kinetic inductance and a nanosecond response time, they are characterized by a low inductance and GHz counting rates. We have designed, simulated, and tested the structures consisting of several, connected in parallel, meander sections, each having a resistor connected in series. Such new, multi-element geometry led to a significant decrease of the device kinetic inductance without the decrease of its active area and QE. The presented improvement in the SSPD performance makes our detectors most attractive for high-speed quantum communications and quantum cryptography applications.
	Address
	Corporate Author				Thesis
	Publisher	Spie	Place of Publication		Editor	Dusek, M.; Hillery, M.S.; Schleich, W.P.; Prochazka, I.; Migdall, A.L.; Pauchard, A.
	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	1249
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	Author	Okunev, O.; Chulkova, G.; Milostnaya, I.; Antipov, A.; Smirnov, K.; Morozov, D.; Korneev, A.; Voronov, B.; Gol’tsman, G.; Slysz, W.; Wegrzecki, M.; Bar, J.; Grabiec, P.; Górska, 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	2008	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	7009	Issue		Pages	70090V (1 to 8)
	Keywords	SSPD, SNSPD, single-photon detectors, superconductors, superconducting nanost
	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 Î¼m² 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 Î¼m and 1.55 Î¼m 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-heliumstorage 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 < 1.5 ns 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 1s^-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	SPIE	Place of Publication		Editor	Sukhoivanov, I.A.; Svich, V.A.; Shmaliy, Y.S.
	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	1413
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	Author	Zhang, W.; Li, N.; Jiang, L.; Ren, Y.; Yao, Q.-J.; Lin, Z.-H.; Shi, S.-C.; Voronov, B. M.; Gol’tsman, G. N.
	Title	Dependence of noise temperature of quasi-optical superconducting hot-electron bolometer mixers on bath temperature and optical-axis displacement			Type	Conference Article
	Year	2008	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	6840	Issue		Pages	684007 (1 to 8)
	Keywords	NbN HEB mixers, noise temperature, LO power
	Abstract	It is known that the increase of bath temperature results in the decrease of critical current of superconducting hot-electron bolometer (HEB) mixers owing to the depression of superconductivity, thus leading to the degradation of the mixer’s sensitivity. Here we report our study on the effect of bath temperature on the heterodyne mixing performance of quasi-optical superconducting NbN HEB mixers incorporated with a two-arm log-spiral antenna. The correlation between the bath temperature, critical current, LO power requirement and noise temperature is investigated at 0.5 THz. Furthermore, the heterodyne mixing performance of quasi-optical superconducting NbN HEB mixers is examined while there is an optical-axis displacement between the center of the extended hemispherical silicon lens and the superconducting NbN HEB device, which is placed on the back of the lens. Detailed experimental results and analysis are presented.
	Address
	Corporate Author				Thesis
	Publisher	Spie	Place of Publication		Editor	Zhang, C.; Zhang, X.-C.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Terahertz Photonics
	Notes				Approved	no
	Call Number				Serial	1415
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	Author	Slysz, W.; Wegrzecki, M.; Bar, J.; Grabiec, P.; Gorska, M.; Rieger, E.; Dorenbos, P.; Zwiller, V.; Milostnaya, I.; Minaeva, O.; Antipov, A.; Okunev, O.; Korneev, A.; Smirnov, K.; Voronov, B.; Kaurova, N.; Gol’tsman, G.N.; Kitaygorsky, J.; Pan, D.; Pearlman, A.; Cross, A.; Komissarov, I.; Sobolewski, R.
	Title	Fiber-coupled NbN superconducting single-photon detectors for quantum correlation measurements			Type	Conference Article
	Year	2007	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	6583	Issue		Pages	65830J (1 to 11)
	Keywords	NbN SSPD, SNSPD, superconducting single-photon detectors, single-photon detectors, fiber-coupled optical detectors, quantum correlations, superconducting devices
	Abstract	We have fabricated fiber-coupled superconducting single-photon detectors (SSPDs), designed for quantum-correlationtype experiments. The SSPDs are nanostructured ( 100-nm wide and 4-nm thick) NbN superconducting meandering stripes, operated in the 2 to 4.2 K temperature range, and known for ultrafast and efficient detection of visible to nearinfrared photons with almost negligible dark counts. Our latest devices are pigtailed structures with coupling between the SSPD structure and a single-mode optical fiber achieved using a micromechanical photoresist ring placed directly over the meander. The above arrangement withstands repetitive thermal cycling between liquid helium and room temperature, and we can reach the coupling efficiency of up to 33%. The system quantum efficiency, measured as the ratio of the photons counted by SSPD to the total number of photons coupled into the fiber, in our early devices was found to be around 0.3 % and 1% for 1.55 &mgr;m and 0.9 &mgr;m photon wavelengths, respectively. The photon counting rate exceeded 250 MHz. The receiver with two SSPDs, each individually biased, was placed inside a transport, 60-liter liquid helium Dewar, assuring uninterrupted operation for over 2 months. Since the receiver’s optical and electrical connections are at room temperature, the set-up is suitable for any applications, where single-photon counting capability and fast count rates are desired. In our case, it was implemented for photon correlation experiments. The receiver response time, measured as a second-order photon cross-correlation function, was found to be below 400 ps, with timing jitter of less than 40 ps.
	Address
	Corporate Author				Thesis
	Publisher	Spie	Place of Publication		Editor	Dusek, M.; Hillery, M.S.; Schleich, W.P.; Prochazka, I.; Migdall, A.L.; Pauchard, A.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Photon Counting Applications, Quantum Optics, and Quantum Cryptography
	Notes				Approved	no
	Call Number				Serial	1431
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	Author	Ryabchun, S.; Tong, C.-yu E.; Blundell, R.; Kimberk, R.; Gol’tsman, G.
	Title	Effect of microwave radiation on the stability of terahertz hot-electron bolometer mixers			Type	Conference Article
	Year	2006	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	6373	Issue		Pages	63730J (1 to 5)
	Keywords	NbN HEB mixers, hot-electron bolometer mixers, stability, Allan variance, LO power fluctuations
	Abstract	We report our studies of the effect of microwave radiation, with a frequency much lower than that corresponding to the energy gap of the superconductor, on the performance of the NbN hot-electron bolometer (HEB) mixer incorporated into a THz heterodyne receiver. It is shown that exposing the HEB mixer to microwave radiation does not result in a significant rise of the receiver noise temperature and degradation of the mixer conversion gain so long as the level of microwave power is small compared to the local oscillator drive. Hence the injection of a small, but controlled amount of microwave radiation enables active compensation of local oscillator power and coupling fluctuations which can significantly degrade the stability of HEB mixer receivers.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Anwar, M.; DeMaria, A.J.; Shur, M.S.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Terahertz Physics, Devices, and Systems
	Notes				Approved	no
	Call Number				Serial	1441
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	Author	Milostnaya, I.; Korneev, A.; Minaeva, O.; Rubtsova, I.; Slepneva, S.; Seleznev, V.; Chulkova, G.; Okunev, O.; Smirnov, K.; Voronov, B.; Gol’tsman, G.; Slysz, W.; Kitaygorsky, J.; Cross, A.; Pearlman, A.; Sobolewski, R.
	Title	Superconducting nanostructured detectors capable of single photon counting of mid-infrared optical radiation			Type	Conference Article
	Year	2005	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	5957	Issue		Pages	59570A (1 to 9)
	Keywords	SSPD, SNSPD, single-photon detectors, superconductors, superconducting
	Abstract	We report on our progress in research and development of ultrafast superconducting single-photon detectors (SSPDs) based on ultrathin NbN nanostructures. Our SSPDs were made of the 4-nm-thick NbN films with T_c 11 K, patterned as meander-shaped, 100-nm-wide strips, and covering an area of 10×10 μm². The detectors exploit a combined detection mechanism, where upon a single-photon absorption, a hotspot of excited electrons and redistribution of the biasing supercurrent, jointly produce a picosecond voltage transient signal across the superconducting nanostripe. The SSPDs are typically operated at 4.2 K, but 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 the optical absorption of our 4-nm-thick NbN film. With the wavelength increase of the incident photons,the QE of SSPDs decreases significantly, but even at the wavelength of 6 μm, the detector is able to count single photons and exhibits QE of about 10^-2 %. The dark (false) count rate at 2 K is as low as 2x10^-4 s,^-1 which makes our detector essentially a background-limited sensor. The very low dark-count rate results in a noise equivalent power (NEP) below 10^-18WHz^-1/2 for the mid-infrared range (6 μm). Further improvement of the SSPD performance in the mid-infrared range can be obtained by substituting NbN for another, lower-T_c materials with a narrow superconducting gap and low quasiparticles diffusivity. The use of such superconductors should shift the cutoff wavelength below 10 μm.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Rogalski, A.; Dereniak, E.L.; Sizov, F.F.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Infrared Photoelectronics
	Notes				Approved	no
	Call Number				Serial	1458
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	Author	Slysz, W.; Wegrzecki, M.; Bar, J.; Grabiec, P.; Górska, M.; Latta, C.; Zwiller, V.; Pearlman, A.; Cross, A.; Korneev, A.; Kouminov, P.; Smirnov, K.; Voronov, B.; Gol’tsman, G.; Verevkin, A.; Currie, M.; Sobolewski, R.
	Title	Fiber-coupled quantum-communications receiver based on two NbN superconducting single-photon detectors			Type	Conference Article
	Year	2005	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	5957	Issue		Pages	59571K (1 to 10)
	Keywords	SSPD, SNSPD, single-photon detectors, quantum communication, quantum cryptography, superconductors, infrared optical detectors
	Abstract	We present the design and performance of a novel, two-channel single-photon receiver, based on two fiber-coupled NbN superconducting single-photon detectors (SSPDs). The SSPDs are nanostructured superconducting meanders covering an area of 100 μm² and are known for ultrafast and efficient counting of single, visible-to-infrared photons. Their operation has been explained within a phenomenological hot-electron photoresponse model. Our receiver is intended for fiber-based quantum cryptography and communication systems, operational at near-infrared (NIR) telecommunication wavelengths, λ = 1.3 μm and λ = 1.55 μm. Coupling between the NbN detector and a single-mode optical fiber was achieved using a specially designed, micromechanical photoresist ring, positioned directly over the SSPD active area. The positioning accuracy of the ring was below 1 μm. The receiver with SSPDs was placed (immersed) in a standard liquid-helium transport Dewar and kept without interruption for over two months at 4.2 K. At the same time, the optical fiber inputs and electrical outputs were kept at room temperature. Our best system reached a system quantum efficiency of up to 0.3 % in the NIR radiation range, with the detector coupling efficiency of about 30 %. The response time was measured to be about 250 ps and was limited by our read-out electronics. The measured jitter was close to 35 ps. The presented performance parameters show that our NIR single photon detectors are suitable for practical quantum cryptography and for applications in quantum-correlation experiments.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Rogalski, A.; Dereniak, E.L.; Sizov, F.F.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Infrared Photoelectronics
	Notes				Approved	no
	Call Number				Serial	1459
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	Author	Hubers, H.-W.; Semenov, A.; Richter, H.; Schwarz, M.; Gunther, B.; Smirnov, K.; Gol’tsman, G.; Voronov, B.
	Title	Heterodyne receiver for 3-5 THz with hot-electron bolometer mixer			Type	Conference Article
	Year	2004	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	5498	Issue		Pages	579-586
	Keywords	NbN HEB mixers
	Abstract	Heterodyne receivers for applications in astronomy and planetary research need quantum limited sensitivity. In instruments which are currently build for SOFIA and Herschel superconducting hot electron bolometers (HEB) will be used to achieve this goal at frequencies above 1.4 THz. The local oscillator and the mixer are the most critical components for a heterodyne receiver operating at 3-5 THz. The design and performance of an optically pumped THz gas laser optimized for this frequency band will be presented. In order to optimize the performance for this frequency 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 x 0.2 Î¼m² incorporated in a logarithmic spiral antenna. The DSB noise temperatures were 2700 K, 4700 K 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	SPIE	Place of Publication		Editor	Zmuidzinas, J.; Holland, W.S.; Withington, S.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Millimeter and Submillimeter Detectors for Astronomy II
	Notes				Approved	no
	Call Number				Serial	1483
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	Author	Hoogeveen, R. W. M.; Yagoubov, P. A.; Maurellis, A.; Koshelets, V. P.; Shitov, S. V.; Mair, U.; Krocka, M.; Wagner, G.; Birk, M.; Huebers, H.-W.; Richter, H.; Semenov, A.; Gol’tsman, G. N.; Voronov, B. M.; Ellison, B.N.; Kerridge, B.J.; Matheson, D. N.; Alderman, B.; Harman, M.; Siddans, R.; Reburn, J.
	Title	New cryogenic heterodyne techniques applied in TELIS: the balloonborne THz and submillimeter limb sounder for atmospheric research			Type	Conference Article
	Year	2003	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	5152	Issue		Pages	347-355
	Keywords	TELIS, limb sounder, heterodyne detection, terahertz, sub millimeter, cryogenic, limb sounding, balloon borne, atmospheric research
	Abstract	We present a design concept for a new state-of-the-art balloon borne atmospheric monitor that will allow enhanced limb sounding of the Earth’s atmosphere within the submillimeter and far-infrared wavelength spectral range: TELIS, TErahertz and submm LImb Sounder. The instrument is being developed by a consortium of major European institutes that includes the Space Research Organization of the Netherlands (SRON), the Rutherford Appleton Laboratory (RAL) will utilize state-of-the-art superconducting heterodyne technology and is designed to be a compact, lightweight instrument cpaable of providing broad spectral coverage, high spectral resolution and long flight duration ( 24 hours duration during a single flight campaign). The combination of high sensitivity and extensive flight duration will allow evaluation of the diurnal variation of key atmospheric constitutenets sucyh as OH, HO2, ClO, BrO togehter will onger lived constituents such as O₃, HCL and N₂O. Furthermore, TELIS will share a common balloon platform to that of the MIPAS-B Fourier Transform Spectrometer, developed by the Institute of Meteorology and Climate research of the over an extended spectral range. The combination of the TELIS and MIPAS instruments will provide atmospheric scientists with a very powerful observational tool. TELIS will serve as a testbed for new cryogenic heterodyne detection techniques, and as such it will act as a prelude to future spaceborne instruments planned by the European Space Agency (ESA).
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Strojnik, M.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Infrared Spaceborne Remote Sensing XI
	Notes				Approved	no
	Call Number				Serial	1508
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	Author	Verevkin, A. A.; Pearlman, A.; Slysz, W.; Zhang, J.; Sobolewski, R.; Chulkova, G.; Okunev, O.; Kouminov, P.; Drakinskij, V.; Smirnov, K.; Kaurova, N.; Voronov, B.; Gol’tsman, G.; Currie, M.
	Title	Ultrafast superconducting single-photon detectors for infrared wavelength quantum communications			Type	Conference Article
	Year	2003	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	5105	Issue		Pages	160-170
	Keywords	NbN SSPD, SNSPD, applications, single-photon detector, quantum cryptography, quantum communications, superconducting devices
	Abstract	We have developed a new class of superconducting single-photon detectors (SSPDs) for ultrafast counting of infrared (IR) photons for secure quantum communications. The devices are operated on the quantum detection mechanism, based on the photon-induced hotspot formation and subsequent appearance of a transient resistive barrier across an ultrathin and submicron-wide superconducting stripe. The detectors are fabricated from 3.5-nm-thick NbN films and they operate at 4.2 K inside a closed-cycle refrigerator or liquid helium cryostat. Various continuous and pulsed laser sources have been used in our experiments, enabling us to determine the detector experimental quantum efficiency (QE) in the photon-counting mode, response time, time jitter, and dark counts. Our 3.5-nm-thick SSPDs reached QE above 15% for visible light photons and 5% at 1.3 – 1.5 Î¼m infrared range. The measured real-time counting rate was above 2 GHz and was limited by the read-out electronics (intrinsic response time is <30 ps). The measured jitter was <18 ps, and the dark counting rate was <0.01 per second. The measured noise equivalent power (NEP) is 2 x 10^-18 W/Hz^1/2 at Î» = 1.3 Î¼m. In near-infrared range, in terms of the counting rate, jitter, dark counts, and overall sensitivity, the NbN SSPDs significantly outperform their semiconductor counterparts. An ultrafast quantum cryptography communication technology based on SSPDs is proposed and discussed.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Donkor, E.; Pirich, A.R.; Brandt, H.E.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Quantum Information and Computation
	Notes				Approved	no
	Call Number				Serial	1514
Permanent link to this record



	Author	Verevkin, A. A.; Zhang, J.; Slysz, W.; Sobolewski, R.; Lipatov, A. P.; Okunev, O.; Chulkova, G.; Korneev, A.; Gol’tsman, G. N.
	Title	Superconducting single-photon detectors for GHz-rate free-space quantum communications			Type	Conference Article
	Year	2002	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	4821	Issue		Pages	447-454
	Keywords	NbN SSPD, SNSPD, single-photon detector, thin-film superconductivity, quantum cryptography, ultrafast communications
	Abstract	We report our studies on the performance of new NbN ultrathin-film superconducting single-photon detectors (SSPDs). Our SSPDs exhibit experimentally measured quantum efficiencies from 5% at wavelength λ = 1550 nm up to 10% at λ = 405 nm, with exponential, activation-energy-type spectral sensitivity dependence in the 0.4-μm – 3-μm wavelength range. Using a variable optical delay setup, we have shown that our NbN SSPDs can resolve optical photons with a counting rate up to 10 GHz, presently limited by the read-out electronics. The measured device jitter was below 35 ps under optimum biasing conditions. The extremely high photon counting rate, together with relatively high (especially for λ > 1 μm) quantum efficiency, low jitter, and very low dark counts, make NbN SSPDs very promising for free-space communications and quantum cryptography.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Ricklin, J.C.; Voelz, D.G.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Free-Space Laser Communication and Laser Imaging II
	Notes				Approved	no
	Call Number				Serial	1523
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	Author	Huebers, H.-W.; Semenov, A.; Schubert, J.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Krabbe, A.; Roeser, H.-P.
	Title	NbN hot-electron bolometer as THz mixer for SOFIA			Type	Conference Article
	Year	2000	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	4014	Issue		Pages	195-202
	Keywords	NbN HEB mixers, airborne, stratospheric observatory, SOFIA
	Abstract	Heterodyne receivers for applications in astronomy need quantum limited sensitivity. We have investigated phonon- cooled NbN hot electron bolometric mixers in the frequency range from 0.7 THz to 5.2 THz. The devices were 3.5 nm thin films with an in-plane dimension of 1.7 X 0.2 micrometers ² integrated in a complementary logarithmic spiral antenna. The best measured DSB receiver noise temperatures are 1300 K (0.7 THz), 2000 K (1.4 THz), 2100 K (1.6 THz), 2600 K (2.5 THz), 4000 K (3.1 THz), 5600 K (4.3 THz), and 8800 K (5.2 THz). The sensitivity fluctuation, the long term stability, and the antenna pattern were measured. The results demonstrate that this mixer is very well suited for GREAT, the German heterodyne receiver for SOFIA.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Melugin, R.K.; Roeser, H.-P.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Airborne Telescope Systems
	Notes				Approved	no
	Call Number				Serial	1554
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	Author	Yngvesson, K. S.; Gerecht, E.; Musante, C. F.; Zhuang, Y.; Ji, M.; Goyette, T. M.; Dickinson, J. C.; Waldman, J.; Yagoubov, P. A.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
	Title	Low-noise HEB heterodyne receivers and focal plane arrays for the THz regime using NbN			Type	Conference Article
	Year	1999	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	3795	Issue		Pages	357-368
	Keywords	NbN HEB mixers
	Abstract	We have developed prototype HEB receivers using thin film superconducting NbN devices deposited on silicon substrates. The devices are quasi-optically coupled through a silicon lens and a self-complementary log-specific toothed antenna. We measured DSB receiver noise temperatures of 500 K (13 X hf/2k) at 1.56 THz and 1,100 K (20 X hf/2k) at 2.24 THz. Noise temperatures are expected to fall further as devices and quasi-optical coupling methods are being optimized. The measured 3 dB IF conversion gain bandwidth for one device was 3 GHz, and it is estimated that the bandwidth over which the receiver noise temperature is within 3 dB of its minimum value is 6.5 GHz which is sufficient for a number of practical applications. We will discuss our latest results and give a detailed description of our prototype setup and experiments. We will also discuss our plans for developing focal plane arrays with tens of Hot Electron Bolometric mixer elements on a single silicon substrate which will make real time imaging systems in the THz region feasible.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Hwu, R.J.; Wu, K.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Terahertz and Gigahertz Photonics
	Notes				Approved	no
	Call Number				Serial	1561
Permanent link to this record



	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
Permanent link to this record



	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	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
Permanent link to this record



	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	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	Baselmans, J. J. A.; Hajenius, M.; Gao, J.; de Korte, P.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G.
	Title	Doubling of sensitivity and bandwidth in phonon-cooled hot-electron bolometer mixers			Type	Conference Article
	Year	2004	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
	Volume	5498	Issue		Pages	168-176
	Keywords	Hot electron bolometers, bandwidth, noise temperature, experimental
	Abstract	NbN hot electron bolometer (HEB) mixers are at this moment the best heterodyne detectors for frequencies above 1 THz. However, the fabrication procedure of these devices is such that the quality of the interface between the NbN superconducting film and the contact structure is not under good control. This results in a contact resistance between the NbN bolometer and the contact pad. We compare identical bolometers, with different NbN – contact pad interfaces, coupled with a spiral antenna. We find that cleaning the NbN interface and adding a thin additional superconductor prior to the gold contact deposition improves the noise temperature and the bandwidth of the HEB mixers with more than a factor of 2. We obtain a DSB noise temperature of 950 K at 2.5 THz and a Gain bandwidth of 5-6 GHz. For use in real receiver systems we design small volume (0.15x1 micron) HEB mixers with a twin slot antenna. We find that these mixers combine good sensitivity (900 K at 1.6 THz) with low LO power requirement, which is 160 – 240 nW at the Si lens of the mixer. This value is larger than expected from the isothermal technique and the known losses in the lens by a factor of 3-3.5.
	Address
	Corporate Author				Thesis
	Publisher	SPIE	Place of Publication		Editor	Zmuidzinas, J.; Holland, W.S.; Withington, S.
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference	Millimeter and Submillimeter Detectors for Astronomy II
	Notes				Approved	no
	Call Number				Serial	1744
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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	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	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	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	Blagosklonskaya, L. E.; Gershenzon, E. M.; Gol’tsman, G. N.; Elant’ev, A. I.
	Title	Effect of a strong magnetic field on the spectrum of donors in InSb			Type	Journal Article
	Year	1978	Publication	Sov. Phys. Semicond.	Abbreviated Journal	Sov. Phys. Semicond.
	Volume	11	Issue	12	Pages	1395-1397
	Keywords	InSb, spectrum of donors, strong magnetic field
	Abstract
	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	1725
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	Author	Korneev, A.; Divochiy, A.; Tarkhov, M.; Minaeva, O.; Seleznev, V.; Kaurova, N.; Voronov, B.; Okunev, O.; Chulkova, G.; Milostnaya, I.; Smirnov, K.; Gol’tsman, G.
	Title	Superconducting NbN-nanowire single-photon detectors capable of photon number resolving			Type	Conference Article
	Year	2008	Publication	Supercond. News Forum	Abbreviated Journal	Supercond. News Forum
	Volume		Issue		Pages
	Keywords	PNR SSPD, SNSPD
	Abstract	We present our latest generation of ultra-fast superconducting NbN single-photon detectors (SSPD) capable of photon-number resolving (PNR). The novel SSPDs combine 10 μm x 10 μm active area with low kinetic inductance and PNR capability. That resulted in significantly reduced photoresponse pulse duration, allowing for GHz counting rates. The detector’s response magnitude is directly proportional to the number of incident photons, which makes this feature easy to use. We present experimental data on the performance of the PNR SSPDs. These detectors are perfectly suited for fibreless free-space telecommunications, as well as for ultra-fast quantum cryptography and quantum computing.
	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	Reference No. ST34, paper # 012307, eventually not pulished (skipped) at https://iopscience.iop.org/issue/0953-2048/21/1			Approved	no
	Call Number	RPLAB @ sasha @ korneevsuperconducting			Serial	1046
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	Author	Yang, Z. Q.; Hajenius, M.; Baselmans, J. J. A.; Gao, J. R.; Voronov, B.; Gol’tsman, G. N.
	Title	Reduced noise in NbN hot-electron bolometer mixers by annealing			Type	Journal Article
	Year	2006	Publication	Supercond. Sci. Technol.	Abbreviated Journal	Supercond. Sci. Technol.
	Volume	19	Issue	4	Pages	L (9 to 12)
	Keywords	NbN HEB mixers
	Abstract	We find that the sensitivity of heterodyne receivers based on superconducting hot-electron bolometers (HEBs) increases by 25–30% after annealing at 85 °C in vacuum. The devices studied are twin-slot antenna coupled mixers with a small NbN bridge of 1 × 0.15 µm2. We show that annealing changes the device properties as reflected in sharper resistive transitions of the complete device, apparently reducing the device-related noise. The lowest receiver noise temperature of 700 K is measured at a local oscillator frequency of 1.63 THz and a bath temperature of 4.3 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	0953-2048	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1456
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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	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.; 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	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	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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