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Author	Il'in, K.; Siegel, M.; Semenov, A.; Engel, A.; Hübers, H.-W.; Hollmann, E.; Gol'tsman, G.; Voronov, B.
Title	Thickness dependence of superconducting properties of ultrathin Nb and NbN films			Type	Conference Article
Year	2004	Publication	AKF-Frühjahrstagung	Abbreviated Journal
Volume		Issue		Pages
Keywords	Nb, NbN films, has potential plagiarism
Abstract
Address	Berlin-Adlershof
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	1503
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Author	Semenov, A.; Richter, H.; Hübers, H.-W.; Smirnov, K.; Voronov, B.; Gol'tsman, G.
Title	Development of terahertz superconducting hot-electron bolometer mixers			Type	Conference Article
Year	2003	Publication	Proc. 6th European Conf. Appl. Supercond.	Abbreviated Journal	Proc. 6th European Conf. Appl. Supercond.
Volume	181	Issue		Pages	2960-2965
Keywords	NbN HEB mixers
Abstract	We present recent results of the development of phonon cooled hot-electron bolometric (HEB) mixers for airborne and balloon borne terahertz heterodyne receivers. Three iomportant issues have been addresses: the quality of NbN films the HEB mixers were made from, the spectral properties of the HEB mixers and the local oscillator power required for optical operation. Studies with an atomic force microscope indicate, that the performance of the HEB mixer might have been effected by the microstructure of the NbN film. Antenna gain and noise temperature were investigated at terahertz frequencies for a HEB embedded in either log-spiral or twin-slot feed antenna. Comparison suggests that at frequencies above 3 THz the spiral feed provides better overall performance. At 1.6 THz, a power of 2.5 µW was required from the local oscillator for optimal operation of the HEB mixer.
Address	Sorrento, Italy
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	0750309814, 978-0750309813	Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1505
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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	Rubtsova, I.; Korneev, A.; Matvienko, V.; Chulkova, G.; Milostnaya, I.; Goltsman, G.; Pearlman, A.; Slysz, W.; Verevkin, A.; Sobolewski, R.
Title	Spectral sensitivity, quantum efficiency, and noise equivalent power of NbN superconducting single-photon detectors in the IR range			Type	Conference Article
Year	2004	Publication	Proc. 29th IRMMW / 12th THz	Abbreviated Journal	Proc. 29th IRMMW / 12th THz
Volume		Issue		Pages	461-462
Keywords	NbN SSPD, SNSPD
Abstract	We have developed nanostructured NbN superconducting single-photon detectors capable of GHz-rate photon counting in the 0.4 to 5 /spl mu/m wavelength range. Quantum efficiency of 30%, dark count rate 3/spl times/10/sup -4/ s/sup -1/, and NEP=10/sup -20/ W/Hz/sup -1/2/ have been measured at the 1.3-/spl mu/m wavelength for the device operating at 2.0 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		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1507
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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	Zhang, J.; Pearlman, A.; Slysz, W.; Verevkin, A.; Sobolewski, R.; Wilsher, K.; Lo, W.; Okunev, O.; Korneev, A.; Kouminov, P.; Chulkova, G.; Gol’tsman, G. N.
Title	A superconducting single-photon detector for CMOS IC probing			Type	Conference Article
Year	2003	Publication	Proc. 16-th LEOS	Abbreviated Journal	Proc. 16-th LEOS
Volume	2	Issue		Pages	602-603
Keywords	NbN SSPD, SNSPD
Abstract	In this paper, a novel, time-resolved, NbN-based, superconducting single-photon detector (SSPD) has been developed for probing CMOS integrated circuits (ICs) using photon emission timing analysis (PETA).
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	The 16th Annual Meeting of the IEEE Lasers and Electro-Optics Society, 2003. LEOS 2003.
Notes				Approved	no
Call Number				Serial	1510
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Author	Sobolewski, R.; Zhang, J.; Slysz, W.; Pearlman, A.; Verevkin, A.; Lipatov, A.; Okunev, O.; Chulkova, G.; Korneev, A.; Smirnov, K.; Kouminov, P.; Voronov, B.; Kaurova, N.; Drakinsky, V.; Goltsman, G. N.
Title	Ultrafast superconducting single-photon optical detectors			Type	Conference Article
Year	2003	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	5123	Issue		Pages	1-11
Keywords	NbN SSPD, SNSPD
Abstract	We present a new class of single-photon devices for counting of both visible and infrared photons. Our superconducting single-photon detectors (SSPDs) are characterized by the intrinsic quantum efficiency (QE) reaching up to 100%, above 10 GHz counting rate, and negligible dark counts. The detection mechanism is based on the photon-induced hotspot formation and subsequent appearance of a transient resistive barrier across an ultrathin and submicron-wide superconducting stripe. The devices are fabricated from 3.5-nm-thick NbN films and operate at 4.2 K, well below the NbN superconducting transition temperature. Various continuous and pulsed laser sources in the wavelength range from 0.4 Î¼m up to >3 Î¼m were implemented in our experiments, enabling us to determine the detector QE in the photon-counting mode, response time, and jitter. For our best 3.5-nm-thick, 10Ã—10 Î¼m²-area devices, QE was found to reach almost 100% for any wavelength shorter than about 800 nm. For longer-wavelength (infrared) radiation, QE decreased exponentially with the photon wavelength increase. Time-resolved measurements of our SSPDs showed that the system-limited detector response pulse width was below 150 ps. The system jitter was measured to be 35 ps. In terms of the counting rate, jitter, and dark counts, the NbN SSPDs significantly outperform their semiconductor counterparts. Already identifeid and implemented applications of our devices range from noninvasive testing of semiconductor VLSI circuits to free-space quantum communications and quantum cryptography.
Address
Corporate Author				Thesis
Publisher	SPIE	Place of Publication		Editor	Spigulis, J.; Teteris, J.; Ozolinsh, M.; Lusis, A.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Advanced Optical Devices, Technologies, and Medical Applications
Notes				Approved	no
Call Number				Serial	1513
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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
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Author	Zhang, J.; Pearlman, A.; Slysz, W.; Verevkin, A.; Sobolewski, R.; Okunev, O.; Korneev, A.; Kouminov, P.; Smirnov, K.; Chulkova, G.; Gol’tsman, G. N.; Lo, W.; Wilsher, K.
Title	Infrared picosecond superconducting single-photon detectors for CMOS circuit testing			Type	Conference Article
Year	2003	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
Volume		Issue		Pages	Cmv4
Keywords	NbN SSPD; SNSPD; Infrared; Quantum detectors; Electron beam lithography; Infrared detectors; Infrared radiation; Quantum efficiency; Single photon detectors; Superconductors
Abstract	Novel, NbN superconducting single-photon detectors have been developed for ultrafast, high quantum efficiency detection of single quanta of infrared radiation. Our devices have been successfully implemented in a commercial VLSI CMOS circuit testing system.
Address
Corporate Author				Thesis
Publisher	Optical Society of America	Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference
Notes				Approved	no
Call Number				Serial	1518
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Author	Baubert, J.; Salez, M.; Delorme, Y.; Pons, P.; Goltsman, G.; Merkel, H.; Leconte, B.
Title	Membrane-based HEB mixer for THz applications			Type	Conference Article
Year	2003	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	5116	Issue		Pages	551-562
Keywords	membrane NbN HEB mixers, heterodyne receiver, stress-less membrane, coupling efficiency, submillimeter-waves frequency, low-cost space applications
Abstract	We report in this paper a new concept for 2.7 THz superconducting Niobium nitride (NbN) Hot-Electron Bolometer mixer (HEB). The membrane process was developped for space telecommnunication applications a few years ago and the HEB mixer concept is now considered as the best choice for low-noise submillimeter-wave frequency heterodyne receivers. The idea is then to join these two technologies. The novel fabrication scheme is to fabricate a NbN HEB mixer on a 1 μm thick stress-less Si₃N₄/SiO₂ membrane. This seems to present numerous improvements concerning : use at higher RF frequencies, power coupling efficiency, HEB mixer sensitivity, noise temperature, and space applications. This work is to be continued within the framework of an ESA TRP project, a 2.7 THz heterodyne camera with numerous applications including a SOFIA airborne receiver. This paper presents the whole fabrication process, the validation tests and preliminary results. Membrane-based HEB mixer theory is currently being investigated and further tests such as heterodyne and Fourier transform spectrometry measurement are planed shortly.
Address
Corporate Author				Thesis
Publisher	SPIE	Place of Publication		Editor	Chiao, J.-C.; Varadan, V.K.; Cané, C.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Smart Sensors, Actuators, and MEMS
Notes				Approved	no
Call Number				Serial	1520
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Author	Cherednichenko, S.; Khosropanah, P.; Adam, A.; Merkel, H. F.; Kollberg, E. L.; Loudkov, D.; Gol'tsman, G. N.; Voronov, B. M.; Richter, H.; Huebers, H.-W.
Title	1.4- to 1.7-THz NbN hot-electron bolometer mixer for the Herschel space observatory			Type	Conference Article
Year	2003	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	4855	Issue		Pages	361-370
Keywords	NbN HEB mixers
Abstract	NbN hot- electron bolometer mixers have reached the level of 10hv/k in terms of the input noise temperature with the noise bandwidth of 4-6 GHz from subMM band up to 2.5 THz. In this paper we discuss the major characteristics of this kind of receiver, i.e. the gain and the noise bandwidth, the noise temperature in a wide RF band, bias regimes and optimisation of RF coupling to the quasioptical mixer. We present the status of the development of the mixer for Band 6 Low for Herschel Telescope.
Address
Corporate Author				Thesis
Publisher	SPIE	Place of Publication		Editor	Phillips, T.G.; Zmuidzinas, J.
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
Notes				Approved	no
Call Number				Serial	1521
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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	Hübers, Heinz-Wilhelm; Semenov, A.; Richter, H.; Smirnov, K.; Gol'tsman, G.; Voronov, B.
Title	Phonon cooled far-infrared hot electron bolometer mixer			Type	Abstract
Year	2002	Publication	NASA/ADS	Abbreviated Journal	NASA/ADS
Volume		Issue		Pages
Keywords	NbN HEB mixers
Abstract	Heterodyne receivers for applications in astronomy need quantum-limited sensitivity. At frequencies above 1.4 THz superconducting hot electron bolometers (HEB) can be used to achieve this goal. We present results of the development of a quasi-optical phonon-cooled NbN HEB mixer for GREAT, the German heterodyne receiver for SOFIA. Different 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 several frequencies between 0.7 THz and 5.2 THz. At 2.5 THz a double sideband noise temperature of 2200 K was achieved. The conversion loss was 16 dB. The response of the mixer was linear up to 400 K load temperature. This performance was verified by measuring an emission line of methanol at 2.5 THz. The results demonstrate that the NbN HEB is very well suited as a mixer for FIR heterodyne receivers.
Address	Monterey, CA
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	Far-IR, Sub-mm & MM Detector Technology Workshop, 1-3 April 2002
Notes	id.37			Approved	no
Call Number				Serial	1534
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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	Semenov, A. D.; Hübers, H.-W.; Richter, H.; Birk, M.; Krocka, M.; Mair, U.; Smirnov, K.; Gol'tsman, G. N.; Voronov, B. M.
Title	2.5 THz heterodyne receiver with NbN hot-electron-bolometer mixer			Type	Journal Article
Year	2002	Publication	Phys. C: Supercond.	Abbreviated Journal	Phys. C: Supercond.
Volume	372-376	Issue		Pages	448-453
Keywords	NbN HEB mixers, applications
Abstract	We describe a 2.5 THz heterodyne receiver for applications in astronomy and atmospheric research. The receiver employs a superconducting NbN phonon-cooled hot-electron-bolometer mixer and an optically pumped far-infrared gas laser as local oscillator. 2200 K double sideband mixer noise temperature was measured at 2.5 THz across a 1 GHz intermediate frequency bandwidth centred at 1.5 GHz. The total conversion losses were 17 dB. The mixer response was linear at load temperatures smaller than 400 K. The receiver was tested in the laboratory environment by measuring the methanol line in emission. Observed pressure broadening confirms the true heterodyne detection regime of the mixer.
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	0921-4534	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1526
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Author	Cherednichenko, S.; Kroug, M.; Merkel, H.; Khosropanah, P.; Adam, A.; Kollberg, E.; Loudkov, D.; Gol'tsman, G.; Voronov, B.; Richter, H.; Huebers, H.-W.
Title	1.6 THz heterodyne receiver for the far infrared space telescope			Type	Journal Article
Year	2002	Publication	Phys. C: Supercond.	Abbreviated Journal	Phys. C: Supercond.
Volume	372-376	Issue		Pages	427-431
Keywords	NbN HEB mixers, applications
Abstract	A low noise heterodyne receiver is being developed for the terahertz range using a phonon-cooled hot-electron bolometric mixer based on 3.5 nm thick superconducting NbN film. In the 1–2 GHz intermediate frequency band the double-sideband receiver noise temperature was 450 K at 0.6 THz, 700 K at 1.6 THz and 1100 K at 2.5 THz. In the 3–8 GHz IF band the lowest receiver noise temperature was 700 K at 0.6 THz, 1500 K at 1.6 THz and 3000 K at 2.5 THz while it increased by a factor of 3 towards 8 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	0921-4534	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1527
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Author	Semenov, Alexei; Hübers, Heinz.-Wilhelm; Richter, Heiko; Birk, Manfred; Krocka, Michael; Mair, Ulrich; Smirnov, Konstantin; Gol'tsman, Grigory; Voronov, Boris
Title	Performance of terahertz heterodyne receiver with a superconducting hot-electron mixer			Type	Conference Article
Year	2002	Publication	Proc. 13^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 13^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	229-234
Keywords
Abstract	During the past decade major advances have been made regarding low noise mixers for terahertz heterodyne receivers. State of the art hot-electron-bolometer (HEB) mixers have noise temperatures close to the quantum limit and require less than a microwatt power from the local oscillator (L0). The technology is now at a point where the performance of a practical receiver employing such mixer, rather than the figures of merit of the mixer itself, is of major concern. We have incorporated a phonon-cooled NbN HEB mixer in a 2.5 THz heterodyne receiver and investigated its performance. This yields important information for future development of heterodyne receivers such as GREAT (German receiver for astronomy at THz frequencies aboard SOFIA) [1] and TELIS (Terahertz limb sounder), a balloon borne heterodyne receiver for atmospheric research [2]. Both are currently under development at DLR.
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	1529
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Author	Loudkov, D.; Khosropanah, P.; Cherednichenko, S.; Adam, A.; MerkeI, H.; Kollberg, E.; Gol'tsman, G.
Title	Broadband fourier transform spectrometer (FTS) measurements of spiral and double-slot planar antennas at THz frequencies			Type	Conference Article
Year	2002	Publication	Proc. 13^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 13^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	373-369
Keywords	NbN HEB mixers
Abstract	The direct responses of NbN phonon-cooled hot electron bolometer (HEB) mixers, integrated with different planar antennas, are measured, using Fourier Transform Spectrometer (F1S). One spiral antenna and several double slot antennas, designed for 0.6, 1.4, 1.6, 1.8 and 2.5 THz central frequencies, are investigated. The Optimization of the measurement set-up is discussed in terms of the beam splitter and the F11S-to-HEB coupling. The result shows that the spiral antenna is circular polarized and has a bandwidth of about 2 THz. The frequency bands of double slot antennas show some shift from the design values and their relative bandwidth increases by increasing the design frequency. The antenna responses do not depend on the HEB bias point and temperature, as long as the device is in the resistive state.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1530
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Author	Okunev, O.; Smirnov, K.; Chulkova, G.; Korneev, A.; Lipatov, A.; Gol'tsman, G.; Zhang, J.; Slysz, W.; Verevkin, A.; Sobolewski, Roman
Title	Ultrafast NBN hot-electron single-photon detectors for electronic applications			Type	Abstract
Year	2002	Publication	Abstracts 8-th IUMRS-ICEM	Abbreviated Journal	Abstracts 8-th IUMRS-ICEM
Volume		Issue		Pages
Keywords	NbN SSPD, SNSPD
Abstract	We present a new, simple to manufacture, single-photon detector (SPD), which can work from ultraviolet to near-infrared wavelengths of optical radiation and combines high speed of operation, high quantum efficiency (QE), and very low dark counts. The devices are superconducting and operate at temperature below 5 K. The physics of operation of our SPD is based on formation of a photon-induced resistive hotspot and subsequent appearance of a transient resistive barrier across an ultrathin and submicron-wide superconductor.
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	8th IUMRS International Conference on Electronic Materials
Notes				Approved	no
Call Number				Serial	1532
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Author	Semenov, Alexei; Hübers, Heinz-Wilhelm; Engel, Andreas; Gol'tsman, Gregory N.
Title	Background limited superconducting quantum detector for astronomy			Type	Abstract
Year	2002	Publication	NASA/ADS	Abbreviated Journal	NASA/ADS
Volume		Issue		Pages
Keywords	SQD
Abstract	We present the concept of the superconducting quantum detector for astronomy. Response to a single absorbed photon appears due to successive formation of a normal spot and phase-slip-centers in a narrow strip carrying sub-critical supercurrent. The detector simultaneously has a moderate energy resolution and a variable cut-off wavelength depending on both the material used and operation conditions. We simulated performance of the background-limited direct detector having the 100- micrometer cut-off wavelength. Low dark count rate will allow to realize 10-21 W Hz-1/2 noise equivalent power at 4 K background radiation. The intrinsic recovery time of the counter is rather determined by diffusion of nonequilibrium electrons, thus, thermal fluctuations do not hamper energy resolution of the detector. Provided an appropriate readout technique, the resolution should be better than 1/20 at 50- micrometer wavelength. Planar layout and relatively simple technology favor integration of the detector into an array.
Address	Monterey, CA
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	Far-IR, Sub-mm & MM Detector Technology Workshop, held 1-3 April 2002
Notes	id.62			Approved	no
Call Number				Serial	1535
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Author	Verevkin, A.; Gershenzon, E. M.; Gol'tsman, G. N.; Ptitsina, N. G.; Chulkova, G. M.; Smirnov, K. S.; Sobolewski, R.
Title	Direct measurements of energy relaxation times in two-dimensional structures under quasi-equilibrium conditions			Type	Conference Article
Year	2002	Publication	Mater. Sci. Forum	Abbreviated Journal	Mater. Sci. Forum
Volume	384-3	Issue		Pages	107-116
Keywords	2DEG, AlGaAs/GaAs
Abstract	A new microwave technique was successfully applied for direct studies of energy relaxation times in two-dimensional AlGaAs/GaAs structures under quasi-equilibrium conditions in the nanosecond and picosecond time scale. We report our results of energy relaxation time measurements in the temperature range 1.6-50 K, in quantum Hall effect regime in magnetic fields up to 4 T.
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	Materials Science Forum
Notes				Approved	no
Call Number				Serial	1536
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Author	Hübers, H.-W.; Semenov, A.; Richter, H.; Birk, M.; Krocka, M.; Mair, U.; Smirnov, K.; Gol’tsman, G.; Voronov, B.
Title	Terahertz Heterodyn Receiver with a hot-electron bolometer mixer			Type	Conference Article
Year	2002	Publication	Far-IR, Sub-mm & MM Detector Technology Workshop	Abbreviated Journal	Far-IR, Sub-mm & MM Detector Technology Workshop
Volume		Issue		Pages	3-24
Keywords	NbN HEB mixers
Abstract	During the past decade major advances have been made regarding low noise mixers for terahertz (THz) heterodyne receivers. State of the art hot-electron-bolometer (HEB) mixers have noise temperatures close to the quantum limit and require less than a µW power from the local oscillator (LO). The technology is now at a point where the performance of a practical receiver employing such mixer, rather than the figures of merit of the mixer itself, are of major concern. We have incorporated a phonon-cooled NbN HEB mixer in a 2.5 THz heterodyne receiver and investigated the performance of the receiver. This yields important information for the development of heterodyne receivers such as GREAT (German receiver for astronomy at THz frequencies aboard SOFIA) [1] and TELIS (Terahertz limb sounder), a balloon borne heterodyne receiver for atmospheric research [2]. Both are currently under development at DLR.
Address
Corporate Author				Thesis
Publisher	NASA	Place of Publication		Editor	Wolf, U.; Farhoomand, J.; McCreight, C.R.
Language		Summary Language		Original Title
Series Editor		Series Title	NASA CP	Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes	Volume: 211408			Approved	no
Call Number				Serial	1537
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Author	Semenov, A.; Hübers, H.-W.; Engel, A.; Gol’tsman, G.
Title	Superconducting quantum detector for far infrared astronomy			Type	Conference Article
Year	2002	Publication	Far-IR, Sub-mm & MM Detector Technology Workshop	Abbreviated Journal	Far-IR, Sub-mm & MM Detector Technology Workshop
Volume		Issue		Pages	3-49
Keywords	SQD
Abstract	We present the concept of the superconducting quantum detector for astronomy. Response to a single absorbed photon appears due to successive formation of a normal spot and phase-slip-centres in a narrow strip carrying sub-critical supercurrent. The detector simultaneously has a moderate energy resolution and a variable cut-off wavelength depending on both the material used and operation conditions. We simulated performance of the background-limited direct detector having the 100-micrometer cut-off wavelength. Low dark count rate will allow to realise 10-21 W Hz-1/2 noise equivalent power at 4 K background radiation. The detection mechanism provides a moderate 1/20 energy resolution at 50-micrometer wavelength.
Address
Corporate Author				Thesis
Publisher	NASA	Place of Publication		Editor	Wolf, J.; Farhoomand, J.; McCreight, C.R.
Language		Summary Language		Original Title
Series Editor		Series Title	NASA CP	Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes	Volume: 211408			Approved	no
Call Number				Serial	1538
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Author	Verevkin, A.; Xu, Y.; Zheng, X.; Williams, C.; Sobolewski, Roman; Okunev, O.; Smirnov, K.; Chulkova, G.; Korneev, A.; Lipatov, A.; Gol’tsman, G. N.
Title	Superconducting NbN-based ultrafast hot-electron single-photon detector for infrared range			Type	Conference Article
Year	2001	Publication	Proc. 12^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 12^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	462-468
Keywords	NbN SSPD, SNSPD
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	1539
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Author	Gol'tsman, Gregory; Semenov, Alexei; Smirnov, Konstantin; Voronov, Boris
Title	Background limited quantum superconducting detector for submillimeter wavelengths			Type	Conference Article
Year	2001	Publication	Proc. 12^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 12^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	469-475
Keywords	Ti SQD, SQUID readout
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	1540
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Author	Xu, Y.; Zheng, X.; Williams, C.; Verevkin, A.; Sobolewski, R.; Chulkova, G.; Lipatov, A.; Okunev, O.; Smirnov, K.; Gol’tsman, G. N.
Title	Ultrafast superconducting hot-electron single-photon detector			Type	Conference Article
Year	2001	Publication	CLEO	Abbreviated Journal	CLEO
Volume		Issue		Pages	345
Keywords	NbN SSPD, SNSPD
Abstract	Summary form only given. The current most-pressing need is to develop a practical, GHz-range counting single-photon detector, operational at either 1.3-/spl mu/m or 1.55-/spl mu/m radiation wavelength, for novel quantum communication and quantum cryptography systems. The presented solution of the problem is to use an ultrafast hot-electron photodetector, based on superconducting thin-film microstructures. This type of device is very promising, due to the macroscopic quantum nature of superconductors. Very fast response time and the small, (meV range) value of the superconducting energy gap characterize the superconductor, leading to the efficient avalanche process even for infrared photons.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Technical Digest. Summaries of papers presented at the Conference on Lasers and Electro-Optics. Postconference Technical Digest (IEEE Cat. No.01CH37170)
Notes				Approved	no
Call Number				Serial	1545
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Author	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	Cherednichenko, S.; Rönnung, F.; Gol'tsman, G.; Kollberg, E.; Winkler, D.
Title	YBa2Cu3O7−δ hot-electron bolometer mixer			Type	Journal Article
Year	2000	Publication	Phys. C: Supercond.	Abbreviated Journal	Phys. C: Supercond.
Volume	341-348	Issue		Pages	2653-2654
Keywords	YBCO HTS HEB mixers
Abstract	We present an investigation of hot-electron bolometric mixer based on YBa2Cu3O7−δ (YBCO) superconducting thin film. Mixer conversion loss, absorbed local oscillator power and intermediate frequency bandwidth was measured at the local oscillator frequency 600 GHz. The fabrication technique for nanoscale YBCO hot-electron bolometer (HEB) mixer integrated into planar antenna structure is described.
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	0921-4534	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1552
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Author	Hübers, Heinz-Wilhelm; Semenov, Alexei; Schubert, Josef; Gol'tsman, Gregory; Voronov, Boris; Gershenzon, Evgeni
Title	Performance of the phonon-cooled hot-electron bolometric mixer between 0.7 THz and 5.2 THz			Type	Conference Article
Year	2000	Publication	Proc. 8-th Int. Conf. on Terahertz Electronics	Abbreviated Journal	Proc. 8-th Int. Conf. on Terahertz Electronics
Volume		Issue		Pages	117-119
Keywords	NbN HEB mixers
Abstract	We report on the phonon cooled NbN hot electron bolometer as mixer in the terahertz frequency range. Its hybrid antenna consists of a hyperhemispheric silicon lens and a logarithmic-spiral feed antenna. Noise temperatures have been measured between 0.7 THz and 5.2 THz. A quarter wavelength layer of Parylene works as antireflection coating for the silicon lens and reduces the noise temperature by about 30. It was found that the antenna pattern at 2.5 THz is determined by the feed antenna and not by the diameter of the lens.
Address	Darmstadt, Germany
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	International Conference on Terahertz Electronics [8th], Held inDarmstadt, Germany on 28-29 September 2000
Notes				Approved	no
Call Number				Serial	1553
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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	Darula, Marian; Semenov, Alex D.; Hübers, Heinz-Wilhelm; Schubert, Josef
Title	Quasioptical high-T_c superconductor Josephson mixer at terahertz frequencies			Type	Abstract
Year	2000	Publication	Proc. 11^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 11^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	515
Keywords	HTS Josephson mixers
Abstract	Mixers based on Josephson junctions from conventional superconductor materials have demonstrated excellent performance at subgap frequencies. The advantages of Josephson mixers are low optimal power of the local oscillator and large intermediate frequency bandwidth but their noise temperature increases dramatically at frequencies corresponding to the energy gap of the superconductor, which is typically below 1 THz for widely used materials. The large energy gap of oxide superconductors makes them promising candidates for development of terahertz Josephson mixers. Here we report on experimental study of the quasioptical mixer utilizing bicrystal Josephson junction from high-transition-temperature YBa 2 Cu 3 O 7-δ film. Junctions with a width of 2 µm were fabricated from 100 nm thick laser ablated films on bicrystal MgO substrates and had the and the J C R n product of about 2 mV at 4.2 K. The planar complementary logarithmic spiral antenna incorporated into co-planar waveguide was patterned from 200 nm thick gold film thermally evaporated in situ on top of the YBa 2 Cu 3 O 7-δ film. The mixer chip was clamped to the extended hemispherical silicon lens. Performance of the mixer was investigated at 4.5 K bath temperature. We used FIR laser as a local oscillator at frequencies 0.698 and 2.52 THz. System noise temperature (DSB) was determined from Y-factor measured with 300 K and 77 K loads. At 0.698 THz the lowest noise temperature 1750 K was observed when the mixer was biased with the fixed current to the region in the vicinity of either the first Shapiro step or the critical current. Between these two bias points the noise temperature increased to ≈ 20000 K. As function of the local oscillator power the noise temperature reached the minimum when the critical current was suppressed to the half of its equilibrium value. Power of the local oscillator absorbed by the mixer at optimal operation was of the order 100 nW. The present design of our antenna limits the upper operation frequency to the value of 1.8 THz. Nevertheless, we clearly observed Shapiro steps at the frequency 2.52 THz. Bearing in mind an improved design of the antenna, we estimate the 3000 K DSB noise temperature at this frequency.
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	1555
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Author	Cherednichenko, S.; Rönnung, F.; Gol’tsman, G.; Kollberg, E.; Winkler, D.
Title	YBa₂Cu₃O_7-δ hot-electron bolometer mixer at 0.6 THz			Type	Conference Article
Year	2000	Publication	Proc. 11^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 11^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	517-522
Keywords	YBCO HTS HEB mixers
Abstract	We present an investigation of hot-electron bolometric mixer based on a YBa 2 Cu 3 O 7-δ (YBCO) superconducting thin film. Mixer conversion loss of –46 dB, absorbed local oscillator power and intermediate frequency bandwidth were measured at the local oscillator frequency 0.6 THz. The fabrication technique for nanoscale YBCO hot-electron bolometer (HEB) mixer integrated with a planar antenna structure is described.
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	1556
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Author	Cherednichenko, S.; Kroug, M.; Yagoubov, P.; Merkel, H.; Kollberg, E.; Yngvesson, K. S.; Voronov, B.; Gol’tsman, G.
Title	IF bandwidth of phonon cooled HEB mixers made from NbN films on MgO substrates			Type	Conference Article
Year	2000	Publication	Proc. 11^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 11^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	219-227
Keywords	NbN HEB mixers, cinversion gain bandwidth, IF bandwidth
Abstract	An investigation of gain and noise bandwidth of phonon-cooled hot-electron bolometric (HEB) mixers is presented. The radiation coupling to the mixers is quasioptical through either a spiral or twin-slot antenna. A maximum gain bandwidth of 4.8 GHz is obtained for mixers based on a 3.5 nm thin NbN film with Tc= 10 K. The noise bandwidth is 5.6 GHz, at the moment limited by parasitic elements in the, device mount fixture. At 0.65 THz the DSB receiver noise temperature is 700-800 К in the IF band 1-2 GHz, and 1150-2700 К in the band 3.5-7 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		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1557
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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
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Author	Cherednichenko, S.; Ronnung, F.; Gol'tsman, G.; Gershenzon, E.; Winkler, D.
Title	YBa₂Cu₃O_7-δ hot-electron bolometer with submicron dimensions			Type	Conference Article
Year	1999	Publication	Proc. 10^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 10^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	181-189
Keywords	YBCO HTS HEB mixers
Abstract	Photoresponse of YBa₂Cu₃O_7-δ hot-electron bolometers to modulated near-infrared radiation was studied at a modulation .frequenc y var y ing from 0.2 MHz to 2 GHz. Bolometers were _fabricated from a 50 12 M thick film and had in-plane areas of 10x10 , um 2 . 2x0.2 s um', 1x0.2 p.m', and 0.5x0.2 jim. We found that nonequilibrium phonons cool down more effectively for the bolometers with smaller area. For the smallest bolometer the bolometric component in the response is 10 dB less than for the largest one.
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	1572
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Author	Schubert, J.; Semenov, A.; Gol'tsman, G.; Hübers, H.-W.; Schwaab, G.; Voronov, B.; Gershenzon, E.
Title	Noise temperature and sensitivity of a NbN hot-electron mixer at frequencies from 0.7 THz to 5.2 THz			Type	Conference Article
Year	1999	Publication	Proc. 10^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 10^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	190-199
Keywords	NbN HEB mixers
Abstract	We report on noise temperature measurements of a NbN phonon-cooled hot-electron bolometric mixer at different bias regimes. The device was a 3 nm thick bridge with in-plane dimensions of 1.7 x 0.2 gm 2 integrated in a complementary logarithmic spiral antenna. Measurements were performed at frequencies ranging from 0.7 THz up to 5.2 THz. The measured DSB noise temperatures are 1500 K (0.7 THz), 2200 K (1.4 THz), 2600 K (1.6 THz), 2900 K (2.5 THz), 4000 K (3.1 THz) 5600 K (4.3 THz) and 8800 K (5.2 THz). Two bias regimes are possible in order to achieve low noise temperatures. But only one of them yields sensitivity fluctuations close to the theoretical limit.
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	1573
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Author	Gerecht, E.; Musante, C. F.; Jian, H.; Zhuang, Y.; Yngvesson, K. S.; Dickinson, J.; Goyette, T.; Waldman, J.; Yagoubov, P. A.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
Title	Improved characteristics of NbN HEB mixers integrated with log-periodic antennas			Type	Conference Article
Year	1999	Publication	Proc. 10^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 10^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	200-207
Keywords	NbN HEB mixers
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	1574
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Author	Yagoubov, P.; Kroug, M.; Merkel, H.; Kollberg, E.; Hübers, H.-W.; Schubert, J.; Schwaab, G.; Gol'tsman, G.; Gershenzon, E.
Title	NbN hot electron bolometric mixers at frequencies between 0.7 and 3.1 THz			Type	Conference Article
Year	1999	Publication	Proc. 10^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 10^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	238-246
Keywords	NbN HEB mixers
Abstract	The performance of NbN based phonon-cooled Hot Electron Bolometric (HEB) quasioptical mixers is investigated in the 0.7-3.1 THz frequency range. The devices are made from a 3.5-4 nm thick NbN film on high resistivity Si and integrated with a planar spiral antenna on the same substrate. The length of the bolometer microbridge is 0.1- 0.2 gm, the width is 1-2 gm. The best results of the DSB receiver noise temperature measured at 1.5 GHz intermediate frequency are: 800 K at 0.7 THz, 1100 K at 1.6 THz, 2000 K at 2.5 THz and 4200 K at 3.1 THz. The measurements were performed with a far infrared laser as the local oscillator (LO) source. The estimated LO power required is less than 500 nW at the receiver input. First results on the spiral antenna polarization measurements are reported.
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	1575
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Author	Il'in, K. S.; Gol'tsman, G. N.; Voronov, B. M.; Sobolewski, Roman
Title	Characterization of the electron energy relaxation process in NbN hot-electron devices			Type	Conference Article
Year	1999	Publication	Proc. 10^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 10^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	390-397
Keywords	HEB mixers, SSPD, SNSPD, NbN films, Nb films
Abstract	We report on transient measurements of electron energy relaxation in NbN films with 300-fs time resolution. Using an electro-optic sampling technique, we have studied the photoresponse of 3.5-nm-thick NbN films deposited on sapphire substrates and exposed to 100-fs-wide optical pulses. Our experimental data analysis was based on the two-temperature model and has shown that in our films at the superconducting transition 10.5 K the inelastic electron-phonon scattering time was about (111}+-__.2) ps. This response time indicated that the maximum intermediate-frequency band of a NbN hot-electron phonon-cooled mixer should reach (16+41-3) GHz if one eliminates the bolometric phonon-heating effect. We have suggested several ways to increase the effectiveness of phonon cooling to achieve the above intrinsic value of the NbN mixer 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	1576
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Author	Schwaab, G. W.; Hübers, H.-W.; Schubert, J.; Erichsen, Patrik; Gol'tsman, G.; Semenov, A.; Verevkin, A.; Cherednichenko, S.; Gershenzon, E.
Title	A high resolution spectrometer for the investigation of molecular structures in the THZ range			Type	Conference Article
Year	1999	Publication	Proc. 10^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 10^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	530-538
Keywords	antireflection coatings, dielectric mirrors
Abstract	A status report on the design study of a novel tunable far-infrared (TuFTR) spectrometer for the investigation of the structure of weakly bound molecular complexes is given. The goal is a sensitive TuFIR spectrometer with full frequency coverage from 1-6 THz. To hit the goal, advanced sources (e.g. p-Ge lasers) and detectors (e.g. superconducting hot electron bolometric (HEB) mixers) shall be employed to extend the technique of cavity ringdown spectroscopy, that is currently used at optical and infrared frequencies to the FIR spectral range. Critical for such a system are high-Q resonators that still allow good optical coupling, and wideband antireflection coatings to increase detector sensitivity and decrease optical path losses. 2 nd order effective media theory and an iterative multilayer algorithm have been employed to design wideband antireflection coatings for dielectrics with large dielectric constants like Ge or Si. Taking into account 6 layers, for Si bandwidths of 100% of the center frequency could be obtained with power reflectivities below 1% for both polarizations simultaneously. Wideband dielectric mirrors including absorption losses were also studied yielding a bandwidth of about 50% with reflectivities larger than 99.5%.
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	1577
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Author	Schubert, J.; Semenov, A.; Hübers, H.-W.; Gol'tsman, G.; Schwaab, G.; Voronov, B.; Gershenzon, E.
Title	Broad-band terahertz NbN hot-electron bolometric mixer			Type	Conference Article
Year	1999	Publication	Inst. Phys. Conf.	Abbreviated Journal	Inst. Phys. Conf.
Volume	167	Issue		Pages	663-666
Keywords	NbN HEB mixers
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	4th Europ. Conf. on Appl. Superconductivity, Barcelona, Spain, 14-17 September 1999
Notes				Approved	no
Call Number				Serial	1578
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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	Schwaab, G.W.; Auen, K.; Bruendermann, E.; Feinaeugle, R.; Gol’tsman, G.N.; Huebers, H.-W.; Krabbe, A.; Roeser, H.-P.; Sirmain, G.
Title	2- to 6-THz heterodyne receiver array for the Stratospheric Observatory for Infrared Astronomy (SOFIA)			Type	Conference Article
Year	1998	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	3357	Issue		Pages	85-96
Keywords	NbN HEB mixers, applications, stratospheric observatory, airborne
Abstract	The Institute of Space Sensor Technology of the German Aerospace Center (DLR) is developing a heterodyne array receiver for the frequency range 2 to 6 THz for the Stratospheric Observatory for Infrared Astronomy (SOFIA). Key science issues in that frequency range are the observation of lines of atoms [e.g. (OI)], ions [e.g. (CII), (NII)], and molecules (e.g. OH, HD, CO) with high spectral resolution to study the dynamics and evolution of galactic and extragalactic objects. Long term goal is the development of an integrated array heterodyne receiver with superconducting hot electron bolometric (HEB) mixers and p-type Ge or Si lasers as local oscillators. The first generation receiver will be composed of HEB mixers in a 2 pixel 2 polarization array which will be pumped by a gas laser local oscillator. Improved Schottky diode mixers are the backup solution for the HEBs. The state of the art of HEB mixer and p-type Ge laser technology are described as well as possible improvements in the ’conventional’ optically pumped far-infrared laser and Schottky diode mixer technology. Finally, the frequency coverage of the first generation heterodyne receiver for some important astronomical transitions is discussed. The expected sensitivity is compared to line fluxes measured by the ISO satellite.
Address
Corporate Author				Thesis
Publisher	SPIE	Place of Publication		Editor	Phillips, T.G.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Advanced Technology MMW, Radio, and Terahertz Telescopes
Notes				Approved	no
Call Number				Serial	1583
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Author	Svechnikov, S.; Verevkin, A.; Voronov, B.; Menschikov, E.; Gershenzon, E.; Gol'tsman, G.
Title	Quasioptical phonon-cooled NbN hot electron bolometer mixers at 0.5-1.1 THz			Type	Conference Article
Year	1998	Publication	Proc. 9^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 9^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	45-51
Keywords	NbN HEB mixers
Abstract	The noise performance of a receiver incorporating spiral antenna coupled NbN phonon-cooled superconducting hot electron bolometric mixer is measured from 450 GHz to 1200 GHz. The mixer element is thin (thickness nm) NbN 1.5 pm wide and 0.2 i.um long film fabricated by lift-off e-beam lithography on high-resistive silicon substrate. The noise of the receiver temperature is 1000 K at 800-900 GHz, 1200 K at 950 GHz, and 1600 K at 1.08 THz. The required (absorbed) local-oscillator power is —20 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		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1586
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Author	Gousev, Yu. P.; Olsson, H. K.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
Title	NbN hot-electron mixer at radiation frequencies between 0.9 THz and 1.2 THz			Type	Conference Article
Year	1998	Publication	Proc. 9^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 9^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	121-129
Keywords	NbN HEB mixers
Abstract	We report on noise temperature measurements for a NbN phonon-cooled hot-electron mixer at radiation frequencies between 0.9 THz and 1.2 THz. Radiation was coupled to the mixer, placed in a vacuum chamber of He cryostat, by means of a planar spiral antenna and a Si immersion lens. A backward-wave oscillator, tunable throughout the spectral range, delivered an output power of few 1.1W that was enough for optimum operation of the mixer. At 4.2 K ambient temperature and 1.025 THz radiation frequency, we obtained a receiver noise temperature of 1550 K despite of using a relatively noisy room-temperature amplifier at the intermediate frequency port. The noise temperature was fairly constant throughout the entire operation range and for intermediate frequencies from 1 GHz to 2 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		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1588
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Author	Yazoubov, P.; Kroug, M.; Merkel, H.; Kollberg, E.; Gol'tsman, G.; Lipatov, A.; Svechnikov, S.; Gershenzon, E.
Title	Quasioptical NbN phonon-cooled hot electron bolometric mixers with low optimal local oscillator power			Type	Conference Article
Year	1998	Publication	Proc. 9^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 9^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	131-140
Keywords	NbN HEB mixers
Abstract	In this paper, the noise perform.ance of NIN based phonon-cooled Hot Electron Bolometric (HEB) quasioptical mixers is investigated in the 0.55-1.1 THz frequency range. The best results of the DSB noise temperature are: 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz and 1250 K at 1.1 THz. The water vapor in the signal path causes a significant contribution to the measured noise temperature around 1.1 THz. The required LO power is typically about 60 nW. The frequency response of the spiral antenna+lens system is measured using a Fourier Transform Spectrometer with the HEB operating in a detector mode.
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	1589
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Author	Il'in, K. S.; Cherednichenko, S. I.; Gol'tsman, G. N.; Currie, M.; Sobolewski, R.
Title	Comparative study of the bandwidth of phonon-cooled NbN hot-electron bolometers in submillimeter and optical wavelength ranges			Type	Conference Article
Year	1998	Publication	Proc. 9^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 9^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	323-330
Keywords	NbN HEB mixers
Abstract	We report the results of the bandwidth measurements of NbN hot-electron bolometers, perfomied in the terahertz frequency domain at 140 GHz and 660 GHz and in time domain in the optical range at the wavelength of 395 nm.. Our studies were done on 3.5-nm-thick NbN films evaporated on sapphire substrates and patterned into ilin-size microbridges. In order to measure the gain bandwidth, we used two identical BWOs (140 or 660 GHz), one functioning as a local oscillator and the other as a signal source. The bandwidth we achieved was 3.5-4 GHz at 4.2 K with the optimal LO and DC biases. Time-domain measurements with a resolution below 300 fs were performed using an electro-optic sampling system, in the temperature range between 4.2 K to 9 K at various values of the bias current and optical power. The obtained response time of the NbN hot-electron bolometer to —100- fs-wide Ti:sapphire laser pulses was about 27 ps, what corresponds to the 5.9 GHz 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	1590
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Author	Karasik, B. S.; Il'in, K. S.; Ptitsina, N. G.; Gol'tsman, G. N.; Gershenzon, E. M.; Pechen', E. V.; Krasnosvobodtsev, S. I.
Title	Electron-phonon scattering rate in impure NbC films			Type	Abstract
Year	1998	Publication	NASA/ADS	Abbreviated Journal	NASA/ADS
Volume		Issue		Pages	Y35.08
Keywords	NbC films
Abstract	The study of the electron-phonon interaction in thin (20 nm) NbC films with electron mean free path l=2-13 nm gives an evidence that electron scattering is significantly modified due to the interference between electron-phonon and elastic electron scattering from impurities. The interference ~T^2-term, which is proportional to the residual resistivity, dominates over the Bloch-Grüneisen contribution to resistivity at low temperatures up to 60 K. The electron energy relaxation rate is directly measured via the relaxation of hot electrons heated by modulated electromagnetic radiation. In the temperature range 1.5 – 10 K the relaxation rate shows a weak dependence on the electron mean free path and strong temperature dependence T^n with the exponent n = 2.5-3. This behaviour is well explained by the theory of the electron-phonon-impurity interference taking into account the electron coupling with transverse phonons determined from the resistivity data.
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	American Physical Society, Annual March Meeting, March 16-20, 1998 Los Angeles, CA
Notes				Approved	no
Call Number				Serial	1591
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Author	Gerecht, E.; Musante, C. F.; Yngvesson, K. S.; Waldman, J.; Gol'tsman, G. N.; Yagoubov, P. A.; Voronov, B. M.; Gershenzon, E. M.
Title	Optical coupling and conversion gain for NbN HEB mixer at THz frequencies			Type	Conference Article
Year	1997	Publication	Proc. 4-th Int. Semicond. Device Research Symp.	Abbreviated Journal	Proc. 4-th Int. Semicond. Device Research Symp.
Volume		Issue		Pages	47-50
Keywords	NbN HEB mixers
Abstract
Address	Charlottesville, Virginia
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	1601
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Author	Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Goltsman, G. N.; Gershenson, E. M.; Yngvesson, K. S.
Title	Direct measurements of electron energy relaxation times at an AlGaAs/GaAs heterointerface in the optical phonon scattering range			Type	Conference Article
Year	1997	Publication	Proc. 4-th Int. Semicond. Device Research Symp.	Abbreviated Journal	Proc. 4-th Int. Semicond. Device Research Symp.
Volume		Issue		Pages	55-58
Keywords	2DEG, AlGaAs/GaAs heterostructures
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	1602
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Author	Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Yngvesson, K. S.
Title	Hot electron bolometer detectors and mixers based on a superconducting-two-dimensional electron gas-superconductor structure			Type	Conference Article
Year	1997	Publication	Proc. 4-th Int. Semicond. Device Research Symp.	Abbreviated Journal	Proc. 4-th Int. Semicond. Device Research Symp.
Volume		Issue		Pages	163-166
Keywords	S-2DEG-S HEB mixers, detectors, AlGaAs/GaAs heterostructures, NbN
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	1603
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Author	Ekström, H.; Kollberg, E.; Yagoubov, P.; Gol'tsman, G.; Gershenzon, E.; Yngvesson, S.
Title	Phonon cooled ultra thin NbN hot electron bolometer mixers at 620 GHz			Type	Conference Article
Year	1997	Publication	Proc. 8^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 8^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	29-35
Keywords	NbN HEB mixers
Abstract	We have measured the noise performance and gain bandwidth of 35 A thin NbN hot-electron mixers integrated with spiral antennas on silicon substrate lenses at 620 GHz. A double-sideband receiver noise temperature less than 1300 K has been obtained with a 3 dB bandwidth of GHz. The gain bandwidth is 3.2 GHz. A lower noise temperature of 1100 K has been achieved with an improved set-up. The mixer output noise dominated by thermal fluctuations is about 50-60 K, and the SSB receiver and intrinsic conversion gain is about -18 and -12 dB, respectively. Without mismatch losses and excluding the loss from the beamsplitter, we expect to achieve a receiver noise temperature of less than 700 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		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1604
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Author	Gerecht, E.; Musante, C. F.; Wang, Z.; Yngvesson, K. S.; Waldman, J.; Gol'tsman, G. N.; Yagoubov, P. A.; Svechnikov, S. I.; Voronov, B. M.; Cherednichenko, S. I.; Gershenzon, E. M.
Title	NbN hot electron bolometric mixer for 2.5 THz: the phonon cooled version			Type	Conference Article
Year	1997	Publication	Proc. 8^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 8^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	258-271
Keywords	NbN HEB mixers
Abstract	We describe an investigation of a NbN HEB mixer for 2.5 THz. NbN HEBs are phonon-cooled de-. vices which are expected, according to theory, to achieve up to 10 GHz IF conversion gain bandwidth. We have developed an antenna coupled device using a log-periodic antenna and a silicon lens. We have demon- strated that sufficient LO power can be coupled to the device in order to bring it to the optimum mixer oper- ating point. The LO power required is less than 1 microwatts as measured directly at the device. We also describe the impedance characteristics of NbN devices and compare them with theory. The experimental results agree with theory except for the imaginary part of the impedance at very low frequencies as was demonstrated by other groups.
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	1605
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Author	Ekström, H.; Kroug, M.; Belitsky, V.; Kollberg, E.; Olsson, H.; Goltsman, G.; Gershenzon, E.; Yagoubov, P.; Voronov, B.; Yngvesson, S.
Title	Hot electron mixers for THz applications			Type	Conference Article
Year	1996	Publication	Proc. 30th ESLAB	Abbreviated Journal	Proc. 30th ESLAB
Volume		Issue		Pages	207-210
Keywords	NbN HEB mixers
Abstract	We have measured the noise performance of 35 A thin NbN HEB devices integrated with spiral antennas on antireflection coated silicon substrate lenses at 620 GHz. From the noise measurements we have determined a total conversion gain of the receiver of—16 dB, and an intrinsic conversion of about-10 dB. The IF bandwidth of the 35 A thick NbN devices is at least 3 GHz. The DSB receiver noise temperature is less than 1450 K. Without mismatch losses, which is possible to obtain with a shorter device, and with reduced loss from the beamsplitter, we expect to achieve a DSB receiver noise temperature of less ‘than 700 K.
Address	Noordwijk, Netherlands
Corporate Author				Thesis
Publisher		Place of Publication		Editor	Rolfe, E. J.; Pilbratt, G.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Submillimetre and Far-Infrared Space Instrumentation
Notes				Approved	no
Call Number				Serial	1606
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Author	Verevkin, A. A.; Ptitsina, N. G.; Chulcova, G. M.; Gol'tsman, G. N.; Gershenzon, E. M.; Yngvesson, K. S.
Title	Direct measurements of energy relaxation time of electrons in AlGaAs/GaAs heterostructures under quasi-equilibrium conditions			Type	Journal Article
Year	1996	Publication	Surface Science	Abbreviated Journal	Surface Science
Volume	361-362	Issue		Pages	569-573
Keywords	2DEG, AlGaAs/GaAs heterostructures
Abstract	For the first time, results are presented of a direct measurement of the energy relaxation time τε of 2D electrons in an AlGaAs/GaAs heterojunction at T = 1 and 5–20 K. A weak temperature dependence of τε for the T > 4K range and a linear temperature dependence of the reciprocal of τε for T < 4K have been observed. The linear dependence τε−1 ≈ T in the Bloch-Gruneisen regime is direct evidence of the predominance of the piezo-electric mechanism of electron-phonon interaction in non-elastic electron scattering processes. The values of τε in this regime are in very good agreement with the results of the Karpus theory. At higher temperatures, where the deformation-potential scattering becomes noticeable, a substantial disagreement between the experimental data and the theoretical results is observed.
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	0039-6028	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1609
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Author	Yagoubov, P.; Gol'tsman, G.; Voronov, B.; Svechnikov, S.; Cherednichenko, S.; Gershenzon, E.; Belitsky, V.; Ekström, H.; Semenov, A.; Gousev, Yu.; Renk, K.
Title	Quasioptical phonon-cooled NbN hot-electron bolometer mixer at THz frequencies			Type	Conference Article
Year	1996	Publication	Proc. 7^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 7^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	303-317
Keywords	NbN HEB mixers
Abstract	In our experiments we tested phonon-cooled hot-electron bolometer (HEB) quasioptical mixer based on spiral antenna designed for 0.5-1.2 THz frequency band and fabricated on sapphire, Si-coated sapphire and high resistivity silicon substrates. HEB devices were produced from thin superconducting NbN film 3.5-6 nm thick with the critical temperature of about 11-12 K. For these devices we achieved the receiver noise temperature T R (DSB) = 3000 K in the 500-700 GHz frequency range and an IF bandwidth of 3-4 GHz. Prelimanary measurements at frequencies 1-1.2 THz resulted the receiver noise temperature about 9000 K (DSB).
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Corporate Author				Thesis
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Language		Summary Language		Original Title
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Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1614
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Author	Trifonov, V. A.; Karasik, B. S.; Zorin, M. A.; Gol'tsman, G. N.; Gershenzon, E. M.; Lindgren, M.; Danerud, M.; Winkler, D.
Title	9.6 μm wavelength mixing in a patterned YBa₂Cu₃O_7-δ thin film			Type	Conference Article
Year	1996	Publication	Proc. 7^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 7^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	337-348
Keywords	YBCO HTS HEB mixers
Abstract	Hot-electron bolometric (HEB) mixing of 9.6 gm infrared radiation from two lasers in high-quality YBa2Cu307_3 (YBCO) patterned thin film has been demonstrated. A heterodyne measurement showed an intermediate frequency (IF) bandwidth of 18 GHz, limited by our measurement system. An intrinsic limit of 100 GHz is predicted. Between 0.1 and 1 GHz intermediate frequency, temperature fluctuations with an equivalent output noise temperature Tfl up to -150 K, contributed to the mixer noise while Johnson noise dominated above 1 GHz. The overall conversion loss at 77 K at low intermediate frequencies was measured to be -25 dB, of which 13 dB was due to the coupling loss. The IIEB mixer is very promising for use in heterodyne receivers within the whole infrared range.
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Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
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Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1615
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Author	Gerecht, E.; Musante, C. F.; Wang, Z.; Yngvesson, K. S.; Mueller, E. R.; Waldman, J.; Gol'tsman, G. N.; Voronov, B. M.; Cherednichenco, S. I.; Svechnikov, S. I.; Yagoubov, P. A.; Gershenzon, E. M.
Title	Optimization of hot eleciron bolometer mixing efficiency in NbN at 119 micrometer wavelength			Type	Conference Article
Year	1996	Publication	Proc. 7^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 7^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	584-600
Keywords	NbN HEB mixers
Abstract	We describe an investigation of a NbN HEB mixer for 2.5 THz. An intrinsic conversion loss of 23 dB has been measured with a two-laser measurement technique. The conversion loss was limited by the LO power available and is expected to decrease to 10 dB or less when sufficient LO power is available. For this initial experiment we used a prototype device which is directly coupled to the laser beams. We present results for a back-short technique that improves the optical coupling to the device and describe our progress for an antenna-coupled device with a smaller dimension. Based on our measured data for conversion loss and device output noise level, we predict that NbN HEB mixers will be capable of achieving DSB receiver noise temperatures of ten times the quantum noise limit in the THz range.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
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Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1616
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Author	Okunev, 0.; Dzardranov, A.; Gol'tsman, G.; Gershenzon, E.
Title	Performances of hot—electron superconducting mixer for frequencies less than the gap energy: NbN mixer for 100 GHz operation			Type	Conference Article
Year	1995	Publication	Proc. 6^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 6^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	247-253
Keywords	NbN HEB mixers
Abstract	The possibilities to improve the parameters of the 100 GHz NbN HEB superconducting waveguide mixers have been studied. The device consists of a signal strip 1 gm wide by 2 Am long made of 40 A thick NbN film. The best operation point was found at 5 K, where the mixer bandwidth made up 1.5-2 GHz and the total loss diminished down to 8 dB. The critical current density has been increased up to " 40 6 A/cm 2 , the noise temperature of the receiver (DSB) has reduced down to 450 K and the local oscillator power has decreased down to -.4).1 mcV.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
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Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1625
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Author	Kawamura, J.; Blundell, R.; Tong, C.-Y. E.; Gol'tsman, G.; Gershenzon, E.; Voronov, B.
Title	NbN hot-electron mixer measurements at 200 GHz			Type	Conference Article
Year	1995	Publication	Proc. 6^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 6^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	254-261
Keywords	NbN HEB mixers
Abstract	We present noise and gain measurements of resistively driven NbN hot-electron mixers near 200 GHz. The device geometry is chosen so that the dominant cooling process of the hot-electrons is their interaction with the lattice. Except for a single batch, the intermediate frequency cut-off of these mixer elements is – 3 700 MHz, and has shown little variation among other batches of devices. At 100 MHz we measured intrinsic mixer losses as low as —3 dB. We measured the noise temperatures at several intermediate frequencies, and for the best de- vice at 137 MHz with 20 MHz bandwidth, we measured 2000 K; using a low-noise first- stage amplifier at 1.5 GHz with 200 MHz bandwidth, the receiver noise temperature measured 2800 K. We estimate that the noise contribution from the mixer is 500 K and the total losses are —15 dB at 137 MHz.
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	1626
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Author	Gol'tsman, G. N.; Karasik, B. S.; Svechnikov, S. I.; Gershenzon, E. M.; Ekström, H.; Kollberg E.
Title	Noise temperature of NbN hot—electron quasioptical superconducting mixer in 200-700 GHz range			Type	Abstract
Year	1995	Publication	Proc. 6^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 6^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	268
Keywords	NbN HEB mixers, noise temperature
Abstract	The electron heating effect in superconducting films is becoming very attractive for the development of THz range mixers because of the absence of frequency limitations inherent in the bolometric mechanism. However, the evidence for the spectral dependence of the position of optimal operating point has been found recently for NbN thin film devices 1.2 • The effect is presumably attributed to the variation in the absorption of radiation depending on the frequency. Since the resistive state is not spatially uniform the coupling efficiency of the mixer device with radiation can be different for frequencies larger than Zeilh and those smaller than 2Alh (d is the effective superconducting gap in the resistive state). To study the effect more thoroughly we have investigated the noise temperature of quasioptical NbN mixer device with broken hue tapered slot antenna in the frequency range 200-700 GHz. The device consists of several (5-10) parallel strips 1 jim wide and 6-7 tun thick made from NbN film on Si0 2 -Si 3 N 4 -Si membrane. The strips are connected with the gold contacts of the slot-line antenna which serves both as bias and IF leads. We used backward wave oscillators as LO sources and a standard hot/cold load technique for noise temperature measurements. The frequency dependence of noise temperature is mainly determined by two factors: frequency properties of the antenna and frequency dependence of the NbN film impedance. To separate both factors we monitored the frequency dependence of the device responsivity in the detector mode at a higher temperature within the superconducting transition where the impedance of NbN film is close to its normal resistance. In this case the impedance of the device itself is frequency independent. The experimental results will be reported at the Symposium. 1. G. Gollsman, S. Jacobsson, H. EkstrOm, B. Karasik, E. Kollberg, and E. Gershenzon, “Slot-line tapered antenna with NbN hot electron mixer for 300-360 GHz operation,” Proc of the 5th Int. Symp. on Space Terahertz Technology, pp. 209-213a, May 10-12,1994. 2. B.S. Karasik, G.N. Gol i tsman, B.M. Voronov, S.I. Svechnikov, E.M. Gershenzon, H. Ekstrom, S. Jacobsson, E. Kollberg, and K.S. Yngvesson, “Hot electron quasioptical NbN superconducting mixer,” presented at the ASC94, submitted to IEEE Trans. on Appl. Superconductivity.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
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Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1627
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Author	Ekström, H.; Karasik, B.; Kollberg, E.; Gol'tsman, G.; Gershenzon, E.
Title	350 GHz NbN hot electron bolometer mixer			Type	Conference Article
Year	1995	Publication	Proc. 6^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 6^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	269-283
Keywords	NbN HEB mixers
Abstract	Superconducting NbN hot-electron bolometer (HEB) mixer devices have been fabricated and measured at 350 GHz. The HEB is integrated with a double dipole antenna on an extended crystalline quartz hyper hemispherical substrate lens. Heterodyne measurement gave a -3 dB bandwidth, mainly determined by the electron- phonon interaction time, of about 680 and 1000 MHz for two different films with Tc = 8.5 and 11 K respectively. The measured DSB receiver noise temperature is around 3000 K at 800 MHz IF frequency. The main contribution to the output noise from the device is due to electron temperature fluctuations with the equivalent output noise temperature TFL-100 K. TH, has the same frequency dependence as the IF response. The contribution from Johnson noise is of the order of T. The RF coupling loss is estimated to be = 6 dB. The film with lower Tc, had an estimated intrinsic low-frequency conversion loss = 7 dB, while the other film had a conversion loss as high as 14 dB. The difference in intrinsic conversion loss is explained by less uniform absorption of radiation. Measurements of the small signal impedance shows a transition of the output impedance from the DC differential resistance Rd=dV/dI in the low frequency limit to the DC resistance R 0 =Uoff 0 in the bias point for frequencies above 3 GHz. We judge that the optimum shape of the IV-characteristic is more easily obtained at THz frequencies where the main restriction in performance should come from problems with the RF coupling.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
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Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1628
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Author	Gerecht, E.; Musante, C. F.; Schuch, R.; Lutz, C. R.; Jr.; Yngvesson, K. S.; Mueller, E. R.; Waldivian, J.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
Title	Hot electron detection and mixing experiments in NbN at 119 micrometer wavelength			Type	Conference Article
Year	1995	Publication	Proc. 6^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 6^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	284-293
Keywords	NbN HEB mixers, detectors
Abstract	We have performed preliminary experiments with the goal of demonstrating a Hot Electron Bolometric (HEB) mixer for a 119 micrometer wavelength (2.5 THz). We have chosen a NbN device of size 700 x 350 micrometers. This device can easily be coupled to a laser LO source, which is advantageous for performing a prototype experiment. The relatively large size of the device means that the LO power required is in the mW range; this power can be easily obtained from a THz laser source. We have measured the amount of laser power actually absorbed in the device, and from this have estimated the best optical coupling loss to be about 10 di . We are developing methods for improving the optical coupling further. Preliminary measurements of the response of the device to a chopped black-body have not yet resulted in a measured receiver noise temperature. We expect to be able to complete this measurement in the near future.
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	1629
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Author	Gershenzon, E. M.; Gol'tsman, G. N.; Zorin, M. A.; Karasik, B. S.; Trifonov, V. A.
Title	Nonequilibrium and bolometric response of YBaCuO films in a resistive state to infrared low intensity radiation			Type	Conference Article
Year	1994	Publication	Council on Low-temp. Phys.	Abbreviated Journal	Council on Low-temp. Phys.
Volume		Issue		Pages	82-83
Keywords	YBCO HTS HEB
Abstract
Address	Dubna
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language	Russian	Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Joint Inst. for Nuclear Research, Dubna (Russian Federation); 296 p; 1994; p. 82-83; 30. Conference on low-temperature physics; 30. Soveshchanie po fizike nizkikh temperatur; Dubna (Russian Federation); 6-8 Sep 1994
Notes	Неравновесный и болометрический отклик YBaCuO пленок в резиотивном состоянии на инфракрасное лазерное излучение малой интенсивности			Approved	no
Call Number				Serial	1632
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Author	Karasik, B.S.; Milostnaya, I.I.; Zorin, M.A.; Elantev, A.I.; Gol'tsman, G.N.; Gershenzon, E.M.
Title	Subnanosecond S-N and N-S switching of YBCO film induced by current pulse			Type	Journal Article
Year	1994	Publication	Phys. C: Supercond.	Abbreviated Journal	Phys. C: Supercond.
Volume	235-240	Issue		Pages	1981-1982
Keywords	YBCO HTS switches
Abstract	A transition of YBCO bridge 60 nm thick from superconducting to normal state induced by an abrupt current step has been studied. A subnanosecond stage has been observed during both S-N and N-S transition. The data obtained can be explained by hot-electron phenomena. On the basis of experimental results a prediction of picosecond switch performance has been made.
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	0921-4534	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1633
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Author	Gol'tsman, G. N.; Kouminov, P.; Goghidze, I.; Gershenzon, E. M.
Title	Nonequilibrium kinetic inductive response of YBaCuO thin films to low-power laser pulses			Type	Journal Article
Year	1994	Publication	Phys. C: Supercond.	Abbreviated Journal	Phys. C: Supercond.
Volume	235-240	Issue		Pages	1979-1980
Keywords	YBCO HTS KID
Abstract	Transient non-equilibrium kinetic inductive voltage response of YBaCuO thin films to 20 ps pulses of YAG:Nd laser radiation with 0.63 μm and 1.5 μm wavelength has been revealed. By increasing the sensitivity of 100 ps resolution time registration system and diminishing light intensity (fluence 0.1-1 μJ2/cm2) and transport current (density j≤105 A/cm2) we observed a perculiar bipolar signal form with nearly equal amplitudes of each sign. The integration of the kinetic inductive response over time gives the result which is qualitatively of the same form as the response in the resistive and normal states: nonequilibrium picosecond scale component followed by bolometric nanosecond. Nonequilibrium response is interpreted as suppression of order parameter by excess of quasiparticles followed by a change in resistance in the resistive state and kinetic inductance in superconductive state.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0921-4534	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1634
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Author	Gol’tsman, G. N.
Title	Terahertz technology in Russia			Type	Conference Article
Year	1994	Publication	24th European Microwave Conf.	Abbreviated Journal	24th European Microwave Conf.
Volume	1	Issue		Pages	113-121
Keywords	BWO, HEB mixers
Abstract	The presentation consider the parameters and operating peculiarities of unique microwave generators of the terahertz range which have been created in Russia – the backward wave oscillators – as well as certain devices based on these generators, such as high resolution. spectrometers and time-resolving spectrometers with picosecond temporal resolution. Most resent BWO-based studies are illustrated by a project devoted to superconductive hot-electron. bolometers which are of great independent value for the terahertz technology as high-sensitive picosecond detectors and low noise broad-band mixers.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	24th European Microwave Conference
Notes				Approved	no
Call Number				Serial	1635
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Author	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
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Author	Gol’tsman, G. N.; Kouminov, P. B.; Goghidze, I. G.; Karasik, B. S.; Gershenzon, E. M.
Title	Nonbolometric and fast bolometric responses of YBaCuO thin films in superconducting, resistive, and normal states			Type	Conference Article
Year	1994	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	2159	Issue		Pages	81-86
Keywords	YBCO HTS HEB, nonbolornetric
Abstract	The transient voltage response in both epitaxial and granular YBaCuO thin films to 20 ps pulses of YAG:Nd laser radiation with 0.63 micrometers and 1.54 micrometers was studied. In normal and resistive states both types of films demonstrate two components: nonequilibrium picosecond component and following bolometric nanosecond. The normalized amplitudes are almost the same for all films. In superconducting state we observed a kinetic inductive response and two-component shape after integration. The normalized amplitude of the response in granular films is up to several orders of magnitude larger than in epitaxial films. We interpret the nonequilibrium response in terms of a suppression of order parameter by the excess of quasiparticles followed by the change of resistance in normal and resistive states or kinetic inductance in superconducting state. The sharp rise of inductive response in granular films is explained both by a diminishing of the crossection for current percolation through the disordered network os Josephson weak links and by a decrease of condensate density in neighboring regions.
Address
Corporate Author				Thesis
Publisher	SPIE	Place of Publication		Editor	Nahum, M.; Villegier, J.-C.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	High-Temperature Superconducting Detectors: Bolometric and Nonbolometric
Notes				Approved	no
Call Number				Serial	1641
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Author	Ekström, H.; Karasik, B.; Kollberg, E.; Yngvesson, K. S.
Title	Investigation of a superconducting hot electron mixer			Type	Conference Article
Year	1994	Publication	Proc. 5^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 5^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	169-188
Keywords	HEB mixers
Abstract	Mixing at 20 GHz in niobium superconducting thin film strips in the resistive state is studied. Experiments give evidence that electron-heating is the main cause of the non linear phenomena. The requirements on the mode of operation and on the film parameters for small conversion loss and the possibility of conversion gain are discussed. Measurements indicate a minimum intrinsic conversion loss around 1 dB with a sharp drop for the lowest voltage bias-points, and a DSB mixer noise temperature between 100 and 450 K at 20 GHz. The device output noise temperature at the mixer operating point can be as low as 30-50 K. A simple theory is presented, which is based on the assumption that the small signal resistance is linearly dependent on power. This type of mixer is considered very promising for use in low-noise heterodyne receivers at THz frequencies.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1642
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Author	Gol'tsman, G.; Jacobsson, S.; Ekstrom, H.; Karasik, B.; Kollberg, E.; Gershenzon, E.
Title	Slot-line tapered antenna with NbN hot electron mixer for 300-360 GHz operation			Type	Conference Article
Year	1994	Publication	Proc. 5^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 5^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	209-213a
Keywords	NbN HEB mixers
Abstract	NbN hot-electron mixers combined with slot-line tapered antennas on Si wdnitride membranes had been fabricated. Several strips of 1 gm wide and 5 tan long made from 100 A NbN film are inserted into the slot antenna. IV-curves under local oscillator power in 300-350 GHz frequency range and conversion gain dependencies on intermediate fre- quency in the 0.1-1 GHz range are measured and compared with that for 100 GHz frequency band. Our results show that pumped IV-curves and intermediate frequency bands are different for 100 GHz and 300 GHz frequency ranges. The interpretation exploits the fact that for the lowest radiation frequency the superconducting energy gap is larger than the radiation quantum energy while they are comparable at the higher frequency. Tha results show that such mixers have good perspectives for terahertz receiving technology.
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	1643
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Author	0kunev, 0.; Dzardanov, A.; Ekstrom, H.; Jacobsson, S.; Kollberg, E.; Gol'tsman, G.; Gershenzon, E.
Title	NbN hot electron waveguide mixer for 100 GHz operation			Type	Conference Article
Year	1994	Publication	Proc. 5^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 5^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	214-224
Keywords	waveguide NbN HEB mixers
Abstract	NbN is a promising superconducting material used to develope hot- electron superconducting mixers with an IF bandwidth over 1 GHz. In the 100 GHz frequency range, the following parameters were obtained for NbN films 50 A thick: the noise temperature of the receiver (DSB) 1000 K; the conversion losses 10 d13, the IF bandwidth 1 GHz; the local oscillator power 1 /LW. An increase of NbN film thickness up to 80-100 A and increase of working temperature up to 7-8 K, and a better mixer matching may allow to broader the IF band up to 3 Gllz, to reduce the conversion losses down to 3-5 dB and the noise tempera- ture down to 200-300 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		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1644
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Author	Elantev, Andrey I.; Karasik, Boris S.
Title	Noise temperature of a superconducting hot-electron mixer			Type	Conference Article
Year	1994	Publication	Proc. 5^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 5^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	225
Keywords	HEB mixers
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	1645
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Author	Gousev, Y. P.; Semenov, A. D.; Gol'tsman, G. N.; Sergeev, A. V.; Gershenzon, E. M.
Title	Electron-phonon interaction in disordered NbN films			Type	Journal Article
Year	1994	Publication	Phys. B Condens. Mat.	Abbreviated Journal	Phys. B Condens. Mat.
Volume	194-196	Issue		Pages	1355-1356
Keywords	NbN films
Abstract	Electron-phonon interaction time has been investigated in disordered films of NbN. A temperatures below 5.5 K tau_eph ~ T -1"6 which is attributed to the renormalisation of phonon spectrum in thin films.
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	0921-4526	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1649
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Author	Ekstrom, H.; Karasik, B.; Weikle, R.; Yngvesson, K. S.; Gol’tsman, G.; Kollberg, E.; Gershenzon, E.
Title	Mixers using superconducting Nb films in the resistive state			Type	Conference Article
Year	1993	Publication	23rd European Microwave Conf.	Abbreviated Journal	23rd European Microwave Conf.
Volume		Issue		Pages	787-789
Keywords	Nb HEB mixers
Abstract	The mixing of 20 GHz radiation in a Nb superconducting film in the resistive state was studied. The experiment gave evidence of electron-heating to be the origin of the non-linear phenomenon. The requirements on the operation mode and on the film parameters in order to obtain small conversion losses or even gain are determined. Our measurements indicate a conversion loss of about 6-8 dB. The hot-electron bolometer is considered to be very promising for use in heterodyne receivers in a wide frequency range from microwaves to terahertz frequencies.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1651
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Author	Gol’tsman, G. N.; 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	Danerud, M.; Winkler, D.; Zorin, M.; Trifonov, V.; Karasik, B.; Gershenzon, E. M.; Gol'tsman, G. N.; Lindgren, M.
Title	Picosecond detection of infrared radiation with YBa₂Cu₃O_7-δ thin films			Type	Conference Article
Year	1993	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	2104	Issue		Pages	183-184
Keywords	YBCO HTS HEB detectors
Abstract	Picosecond nonequilibrium and slow bolometric responses from a patterned high-Tc superconducting (HTS) film due toinfrared radiation were investigated using both modulation and pulse techniques. Measurements at A, = 0.85 [tm andA, = 10.6 lim have shown a similar behaviour of the response vs modulation frequency f. The responsivity of the HTS filmbased detector at f ..- 0.6-1 GHz is estimated to be 10-2 – 10-1 V/W.
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	https://inis.iaea.org/search/searchsinglerecord.aspx?recordsFor=SingleRecord&RN=25034664			Approved	no
Call Number	10.1117/12.2298489			Serial	1653
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Author	Gershenzon, E. M.; Gol'tsman, G. N.
Title	Hot-electron superconducting mixers			Type	Conference Article
Year	1993	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	2104	Issue		Pages	329-330
Keywords
Abstract	The creation of low noise heterodyne receivers for frequencies above 1 THz is in the urgentneed for radio astronomy, laser spectroscopy, plasma diagnostic, etc. In this paper we discussthe nonlinear effect related to hot electrons in superconductors, and their potential use in lownoise submilimeter wave mixer. We also discuss results achieved so far as well as possible futuredevelopments.
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	1654
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Author	Gershenzon, E. M.; Gol'tsman, G. N.
Title	Hot electron superconductive mixers			Type	Conference Article
Year	1993	Publication	Proc. 4^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 4^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	618-622
Keywords	HEB mixers
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	1656
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Author	Gol'tsman, G. N.; Elant'iev, A. I.; Karasik, B. S.; Gershenzon, E. M.
Title	Antenna – coupled superconducting electron-heating bolometer			Type	Conference Article
Year	1993	Publication	Proc. 4^th Int. Symp. Space Terahertz Technol.	Abbreviated Journal	Proc. 4^th Int. Symp. Space Terahertz Technol.
Volume		Issue		Pages	623-628
Keywords	HEB
Abstract	We propose a novel antenna-coupled superconducting bolometer based on electron-heating in the resistive state. A short narrow ultrathin super- conducting film strip (sized approximately 4x1x0.01 pm 3 ), which is in good thermal contact with the thermostat, serves as a resistive load for infrared or submillimeter current. In contrast to conventional isothermal super- conducting bolometers electron-heating ones can have a higher sensitivity which grows when filni. thickness is reduced. Response time of electron- heating bolometer does not depend on heat transfer from the film to the enviroment. To calculate the sensitivity (NEP), we have used experimental data on wideband Al, Nb and NbN bolometers which have the same un- derlying physical mechanism. The bolom.eters have been made in the form of a structure composed of a number of long narrow strips. The values of for Al, NEP have been found to be 1.5 . 113 -16 1 140 -15 ) and 2 . 10 – 14werT,-1/2 – Nb and NbN respectively. In the paper, the prospects are also discussed of improving the picosecond YBaCuO detector, developed recently. NEP value of the detector, if combined with a microantenna, can reach the order of 10- •ilz-v2.
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	1657
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Author	Semenov, A. D.; Sergeev, A. V.; Kouminov, P.; Goghidze, I. G.; Heusinger, M. A.; Nebosis, R. S.; Gol'tsman, G. N.; Gershenzon, E. M.; Renk, K. F.
Title	Transparency of YBCO film/substrate interfaces for thermal phonons determined by photoresponse measurements			Type	Conference Article
Year	1993	Publication	Proc. 1st European Conf. on Appl. Supercond.	Abbreviated Journal	Proc. 1st European Conf. on Appl. Supercond.
Volume	2	Issue		Pages	1443-1446
Keywords	YBCO HTS detectors
Abstract	Direct measurements of the thermal boundary resistance were performed by means of the stationary method. In this approach the temperature of an electrically heated film is controlled by its dc resistance while an additional film on the same substrate is used as a thermometer monitoring substrate temperature. The temperature field in the substrate is then calculated to deduce the Kapitza temperature step at the interface between the heated strip and the substrate. The main statement of all afore-said papers is that experimental values of the thermal boundary resistance are too large to be explained by the acoustic mismatch model. In this paper we investigate transparency of YBaCuO film/substrate interfaces for thermal phonons by means of photoresponse measurements. We show that our data are in reasonable agreement with the acoustic mismatch theory.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor	Freyhardt, H. C.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN	3-88355-197-X	Medium
Area		Expedition		Conference	1st European conference on applied superconductivity
Notes				Approved	no
Call Number				Serial	1661
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Author	Gol’tsman, G. N.; Semenov, A. D.; Sergeev, A. V.; Aksaev, E. E.; Gogidze, I. G.; Gershenzon, E. M.
Title	Electron-phonon interaction in thin YBaCuO films and fast detectors			Type	Conference Article
Year	1993	Publication	Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences	Abbreviated Journal	Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences
Volume	112	Issue		Pages	184-185
Keywords	YBCO HTS detectors
Abstract	The thin. YBaCuO film response to laser and submillimeter radiation demonstrates the picosecond nonequilibrium peak on the nanosecond bolometric background. Experimental data give an evidence for the spectral dependence of picosecond photoresponse probably due to a poor efficiency of electron multiplication processes. Presented results prove an availability of fast YBaCuO thin film detector.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor	Meissner, M.; Pohl, R. O.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Seventh International Conference, Cornell University, Ithaca, New York, August 3-7, 1992
Notes				Approved	no
Call Number				Serial	1662
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Author	Heusinger, M. A.; Nebosis,R. S.; Schatz, W.; Renk, K. F.; Gol’tsman, G. N.; Karasik, B. S.; Semenov, A. D.; Gershenzon, E. M.
Title	Temperature dependence of bolometric and non-bolometric photoresponse of a structured YBa₂Cu₃O_7-δ thin film			Type	Conference Article
Year	1993	Publication	Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences	Abbreviated Journal	Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences
Volume	112	Issue		Pages	193-195
Keywords	YBCO HTS detectors
Abstract	We investigated the temperature dependence of the transient voltage photoresponse of a current biased structured YBa2Cu3O7−δ thin film in its transition temperature region, around 79 K. Both, picosecond nonbolometric and nanosecond bolometric response to ultrashort far-infrared laser pulses were found for frequencies between 25 cm−1 and 215 cm−1. We will discuss optimum conditions for radiation detection and present an analysis of the dynamical behaviour of excited high T c thin films.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor	Meissner, M.; Pohl, R. O.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Seventh International Conference, Cornell University, Ithaca, New York, August 3-7, 1992
Notes				Approved	no
Call Number				Serial	1663
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Author	Sergeev, A. V.; Livanov, D. V.
Title	Phonon renormalization of thermoelectric power of high-T_c materials			Type	Conference Article
Year	1993	Publication	Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences	Abbreviated Journal	Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences
Volume	112	Issue		Pages	204-205
Keywords	HTS, YBCO
Abstract	Renormalization of thermoelectric power due to Nielsen — Taylor effect (interference between electron-phonon and electron- impurity interactions) is used for the explanation of the temperature dependence and sign of the thermopower in high-Tc materials. In the framework of the model the negative sign of TEP of untwinned YBa2Cu3O7−x crystal in a-direction observed by Howson et. al. is connected to the strong hole scattering via O-vacancies in chains.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor	Meissner, M.; Pohl, R. O.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Seventh International Conference, Cornell University, Ithaca, New York, August 3-7, 1992
Notes				Approved	no
Call Number				Serial	1664
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Author	Sergeev, A. V.; Aksaev, E. E.; Gogidze, I. G.; Gol’tsman, G. N.; Semenov, A. D.; Gershenzon, E. M.
Title	Thermal boundary resistance at YBaCuO film-substrate interface			Type	Conference Article
Year	1993	Publication	Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences	Abbreviated Journal	Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences
Volume	112	Issue		Pages	405-406
Keywords	YBCO films
Abstract	The nanosecond voltage response of YBaCuo films on Al2O3, MgO and ZrO2 substrates to electromagnetic radiation of millimeter and visible ranges has been investigated. The analysis of experimental conditions for Al2O3 and MgO substrates shows that the resistance change is monitored by the Kapitza boundary shift of temperature during the temporal interval ~ 100 ns limited by the time of phonon return from a substrate into a film. The observed exponential voltage decay is described by the phonon escape time which is proportional to the film thickness and is weakly temperature dependent.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor	Meissner, M.; Pohl, R. O.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Seventh International Conference, Cornell University, Ithaca, New York, August 3-7, 1992
Notes				Approved	no
Call Number				Serial	1665
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Author	Gershenzon, E. M.; Gol'tsman, G. N.; Semenov, A. D.; Sergeev, A. V.
Title	Heating of electrons in resistive state of superconducting films. Detectors, mixers and switches			Type	Conference Article
Year	1992	Publication	Progress in High Temperature Superconductivity	Abbreviated Journal	Progress in High Temperature Superconductivity
Volume	32	Issue		Pages	190-195
Keywords	superconducting films, heating of electrons
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	International Conference on High Temperature Superconductivity and Localization Phenomena , Moscow, Russia , 11 – 15 May 1991
Notes	https://books.google.co.kr/books?hl=en&lr=&id=uCI0DwAAQBAJ&oi=fnd&pg=PA190&ots=z7WGjXYWr4&sig=TQ6G6dKsmcj4faYe1ZLw_BFmps8			Approved	no
Call Number				Serial	1666
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Author	Kollberg, Erik L.; Gershenzon, E.; Goltsman, G.; Yngvesson, K. S.
Title	Hot electron mixers, the potential competition			Type	Conference Article
Year	1992	Publication	Proc. ESA Symp. on Photon Detectors for Space Instrumentation	Abbreviated Journal	Proc. ESA Symp. on Photon Detectors for Space Instrumentation
Volume		Issue		Pages	201-206
Keywords	HEB mixers
Abstract	There is an urgent need in radio astronomy for low noise heterodyne receivers for frequencies above about 500 GHz. It is not certain that mixers based on superconducting quasiparticle tunnelling (SIS mixers) may turn out to be the answer to this need. In order to try to find an alternative way for realizing low noise heterodyne receivers for submillimeter waves, so called hot electron bolometric effects for mixing are now being investigated. Two basically different approaches are tried, one based on semiconductors and one on superconductors. Both methods are briefly discussed in this overview paper.
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	ESA Symposium on Photon Detectors for Space Instrumentation
Notes				Approved	no
Call Number				Serial	1667
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Author	Gershenzon, E. M.; Gol'tsman, G. N.; Gogidze, I. G.; Semenov, A. D.; Sergeev, A. V.
Title	Processes of electron-phonon interaction in thin YBaCuO films			Type	Journal Article
Year	1991	Publication	Phys. C: Supercond.	Abbreviated Journal	Phys. C: Supercond.
Volume	185-189	Issue		Pages	1371-1372
Keywords	YBCO HTS detectors
Abstract	The ultrafast voltage response of YBaCuO films to laser radiation is studied and compared with previously investigated quasiparicles response to radiation of submillimeter wavelength range. Voltage shift under the visible light radiation has two components. Picosecond response realized as suppression superconductivity by nonequilibrium excess quasiparticles, response time is determined by quasiparticles recombination rate. Nanosecond response is probably due to bolometric effect.
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	0921-4534	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1676
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Author	Varyukhin, S. V.; Zakharov, A. A.; Gershenzon, E. M.; Gol'tsman, G. N.; Ptitsyna, N. G.; Chulkova, G. M.
Title	AC losses and submillimeter absorption in single crystals La2CuO4			Type	Journal Article
Year	1990	Publication	Phys. B Condens. Mat.	Abbreviated Journal	Phys. B Condens. Mat.
Volume	165-166	Issue		Pages	1269-1270
Keywords	metal-dielectric-La2Cu04
Abstract	The La2CuO4 single crystals were used to carry out the measurements of transmission spectra within the submillimeter range of wavelengths, as well as the capacitance C and conductivity G in the region of acoustic frequencies of the metal-dielectric-La2Cu04 system at low temperatures. The optical spectra display a threshold character. There takes place a sharp decreasing of transmission signal in the energy range of hυ>1.5meV. The C(ω,T) and G(ω,T) dependences have a universal form characteristic of relaxation processes of the Debye type. The relaxation time dependence displays a thermoactivation character τ(T)-exp(ξ/T) with a gap value of ξ≃2meV,coinciding with the optical one. It is assumed that there exist excitations with a characteristic energy ~ 2meV in La2Cu04.A possible nature of the revealed low-energy excitations is discussed.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0921-4526	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1686
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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	Gershenzon, E. M.; Goltsman, G. N.; Orlov, L.
Title	Investigation of population and ionization of donor excited states in Ge			Type	Conference Article
Year	1976	Publication	Physics of Semiconductors	Abbreviated Journal	Physics of Semiconductors
Volume		Issue		Pages	631-634
Keywords	Ge, donor excited states
Abstract
Address	Amsterdam
Corporate Author				Thesis
Publisher	North-Holland Publishing Co.	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	1732
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Author	Matyushkin, Yakov; Fedorov, Georgy; Moskotin, Maksim; Danilov, Sergey; Ganichev, Sergey; Goltsman, Gregory
Title	Gate-mediated helicity sensitive detectors of terahertz radiation with graphene-based field effect transistors			Type	Abstract
Year	2020	Publication	Graphene and 2dm Virt. Conf.	Abbreviated Journal	Graphene and 2DM Virt. Conf.
Volume		Issue		Pages
Keywords	single layer graphene, SLG, CVD, plasmons, FET
Abstract	Closing of the so-called terahertz gap results in an increased demand for optoelectronic devices operating in the frequency range from 0.1 to 10 THz. Active plasmonic in field effect devices based on high-mobility two-dimensional electron gas (2DEG) opens up opportunities for creation of on-chip spectrum [1] and polarization [2] analysers. Here we show that single layer graphene (SLG) grown using CVD method can be used for an all-electric helicity sensitive polarization broad analyser of THz radiation. Allourresults show plasmonic nature of response. Devices are made in a configuration ofa field-effect transistor (FET) with a graphene channel that has a length of 2 mkm and a width of 5.5 mkm. Response of opposite polarity to clockwise and anticlockwise polarized radiation is due to special antenna design (see Fig.1c) as follow works [2,3]. Our approaches can be extrapolated to other 2D materials and used as a tool to characterize plasmonic excitations in them. [1]Bandurin, D. A., etal.,Nature Communications, 9(1),(2018),1-8.[2]Drexler, C.,etal.,Journal of Applied Physics, 111(12),(2012),124504.[3]Gorbenko, I. V.,et al.,physica status solidi (RRL)–Rapid Research Letters, 13(3),(2019),1800464.
Address	Grenoble, France
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	Graphene and 2dm Virtual Conference & Expo
Notes				Approved	no
Call Number				Serial	1743
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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	Goltsman, Gregory
Title	Superconducting thin film nanostructures as terahertz and infrared heterodyne and direct detectors			Type	Conference Article
Year	2017	Publication	16th ISEC	Abbreviated Journal	16th ISEC
Volume		Issue		Pages	Th-I-QTE-03 (1 to 3)
Keywords	waveguide SSPD, SNSPD
Abstract	We present our recent achievements in the development of superconducting nanowire single-photon detectors (SNSPDs) integrated with optical waveguides on a chip. We demonstrate both single-photon counting with up to 90% on-chipquantum-efficiency (OCDE), and the heterodyne mixing with a close to the quantum limit sensitivity at the telecommunication wavelength using single device.
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/CSC & ESAS Superconductivity News Forum
Notes				Approved	no
Call Number				Serial	1745
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Author	Gol’tsman, G.N.
Title	Overview of recent results for superconducting NbN terahertz and optical detectors and mixers			Type	Miscellaneous
Year	2014	Publication	SM2 – Seminar on Terahertz Photonics	Abbreviated Journal
Volume		Issue		Pages	0562
Keywords	NbN SSPD, SNSPD, HEB
Abstract	We present our recent achievements in the development of sensitive and ultrafast thin-film superconducting sensors: hot-electron bolometers (HEB), HEB-mixers for terahertz range and infrared single-photon counters. These sensors have already demonstrated a performance that makes them devices-of-choice for many terahertz and optical applications.
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	1746
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Author	Averkin, A. S.; Shishkin, A. G.; Chichkov, V. I.; Voronov, B. M.; Goltsman, G. N.; Karpov, A.; Ustinov, A. V.
Title	Tunable frequency-selective surface based on superconducting split-ring resonators			Type	Conference Article
Year	2014	Publication	8th Metamaterials	Abbreviated Journal	8th Metamaterials
Volume		Issue		Pages
Keywords	superconducting split-ring resonators
Abstract	We study a possibility to use the 2D superconducting metamaterial as a tunable frequency-selective surface (FSS). The proposed FSS is made of sub-wavelength size (l/14) metamaterial unit cells, where a split-ring resonator is embedded in a small iris aperture in a metal plane. The split-ring resonator is made of NbN film, and its resonance frequency is tuned by the temperature of the sample, changing the kinetic inductance of NbN film. The Ansoft HFSS simulation predicts the FSS tuning range of about 10-20 %. The developed superconducting FSS may be used as a tunable band-pass filter or modulator.
Address	Copenhagen, Denmark
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	8th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics – Metamaterials
Notes				Approved	no
Call Number				Serial	1749
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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	Verevkin, A.; Zhang, J.; Pearlman, A.; Slysz, W.; Sobolewski, Roman; Korneev, A.; Kouminov, P.; Okunev, O.; Chulkova, G.; Gol'tsman, G.
Title	Ultimate sensitivity of superconducting single-photon detectors in the visible to infrared range			Type	Miscellaneous
Year	2004	Publication	ResearchGate	Abbreviated Journal	ResearchGate
Volume		Issue		Pages
Keywords	NbN SSPD, SNSPD
Abstract	We present our quantum efficiency (QE) and noise equivalent power (NEP) measurements of the meandertype ultrathin NbN superconducting single-photon detector in the visible to infrared radiation range. The nanostructured devices with 3.5-nm film thickness demonstrate QE up to~ 10% at 1.3–1.55 µm wavelength, and up to 20% in the entire visible range. The detectors are sensitive to infrared radiation with the wavelengths down to~ 10 µm. NEP of about 2× 10-18 W/Hz1/2 was obtained at 1.3 µm wavelength. Such high sensitivity together with GHz-range counting speed, make NbN photon counters very promising for efficient, ultrafast quantum communications and another applications. We discuss the origin of dark counts in our devices and their ultimate sensitivity in terms of the resistive fluctuations in our superconducting nanostructured devices.
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	Not attributed to any publisher! File name: PR9VervekinSfin_f.doc; Author: JAOLEARY; Last modification date: 2004-02-26			Approved	no
Call Number				Serial	1751
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