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Author	Gerecht, E.; Musante, C. F.; Zhuang, Y.; Yngvesson, K. S.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
Title	NbN hot electron bolometric mixerss—a new technology for low-noise THz receivers			Type	Journal Article
Year	1999	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
Volume	47	Issue	12	Pages	2519-2527
Keywords	NbN HEB mixers
Abstract	New advances in hot electron bolometer (HEB) mixers have recently resulted in record-low receiver noise temperatures at terahertz frequencies. We have developed quasi-optically coupled NbN HEB mixers and measured noise temperatures up to 2.24 THz, as described in this paper. We project the anticipated future performance of such receivers to have even lower noise temperature and local-oscillator power requirement as well as wider gain and noise bandwidths. We introduce a proposal for integrated focal plane arrays of HEB mixers that will further increase the detection speed of terahertz systems.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1557-9670	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1560
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Author	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	Gol’tsman, G. N.; Gershenzon, E. M.
Title	Phonon-cooled hot-electron bolometric mixer: overview of recent results			Type	Journal Article
Year	1999	Publication	Appl. Supercond.	Abbreviated Journal	Appl. Supercond.
Volume	6	Issue	10-12	Pages	649-655
Keywords	NbN HEB mixers
Abstract	The paper presents an overview of recent results for NbN phonon-cooled hot electron bolometric (HEB) mixers. The noise temperature of the receivers based on both quasioptical and waveguide versions of HEB mixer has crossed the level of 1 K·GHz−1 at 430 GHz (410 K) and 600–650 GHz (480 K) and is close to this level at 820 GHz (1100 K) and 900 GHz (980 K). The gain bandwidth measured for quasioptical HEB mixer at 620 GHz reached 4 GHz and the noise temperature bandwidth was almost 8 GHz. Local oscillator power requirements are about 1 μW for mixers made by photolithography and are about 100 nW for mixers made by e-beam lithography. The studies in terahertz receivers based on HEB superconducting mixers now present a dynamic, rapidly developing field.
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	0964-1807	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1564
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Author	Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Voronov, B. M.; Gol’tsman, G. N.; Gershenson, E. M.; Yngvesson, K. S.
Title	Multiple Andreev reflection in hybrid AlGaAs/GaAs structures with superconducting NbN contacts			Type	Journal Article
Year	1999	Publication	Semicond.	Abbreviated Journal	Semicond.
Volume	33	Issue	5	Pages	551-554
Keywords	2DEG, AlGaAs/GaAs heterostructures
Abstract	The conductivity of hybrid microstructures with superconducting contacts made of niobium nitride to a semiconductor with a two-dimensional electron gas in a AlGaAs/GaAs heterostructure has been investigated. Distinctive features of the behavior of the conductivity indicate the presence of multiple Andreev reflection at scattering centers in the normal region near the superconductor-semiconductor boundary.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1063-7826	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1571
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Author	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	Men’shchikov, E. M.; Gogidze, I. G.; Sergeev, A. V.; Elant’ev, A. I.; Kuminov, P. B.; Gol’tsman, G. N.; Gershenzon, E. M.
Title	Superconducting fast detector based on the nonequilibrium inductance response of a film of niobium nitride			Type	Journal Article
Year	1997	Publication	Tech. Phys. Lett.	Abbreviated Journal	Tech. Phys. Lett.
Volume	23	Issue	6	Pages	486-488
Keywords	NbN KID
Abstract	A new type of fast detector is proposed, whose operation is based on the variation of the kinetic inductance of a superconducting film caused by nonequilibrium quasiparticles created by the electromagnetic radiation. The speed of the detector is determined by the rate of multiplication of photo-excited quasiparticles, and is nearly independent of the temperature, being less than 1 ps for NbN. Models based on the Owen-Scalapino scheme give a good description of the experimentally determined dependence of the power-voltage sensitivity of the detector on the modulation frequency. The lifetime of the quasiparticles is determined, and it is shown that the reabsorption of nonequilibrium phonons by the condensate has a substantial effect even in ultrathin NbN films 5 nm thick, and results in the maximum possible quantum yield. A low concentration of equilibrium quasiparticles and a high quantum yield result in a detectivity D=1012 W−1·Hz1/2 at a temperature T=4.2 K and D=1016 W−1·cm· Hz1/2 at T=1.6 K.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1063-7850	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1593
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Author	Semenov, A. D.; Gousev, Y. P.; Nebosis, R. S.; Renk, K. F.; Yagoubov, P.; Voronov, B. M.; Gol’tsman, G. N.; Syomash, V. D.; Gershenzon, E. M.
Title	Heterodyne detection of THz radiation with a superconducting hot‐electron bolometer mixer			Type	Journal Article
Year	1996	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
Volume	69	Issue	2	Pages	260-262
Keywords	NbN HEB mixers
Abstract	We report on the use of a superconducting hot‐electron bolometer mixer for heterodyne detection of terahertz radiation. Radiation with a wavelength of 119 μm was coupled to the mixer, a NbN microbridge, by a hybrid quasioptical antenna consisting of an extended hyperhemispherical lens and a planar logarithmic spiral antenna. We found, at an intermediate frequency of 1.5 GHz, a system double side band noise temperature of ≊40 000 K and conversion losses of 25 dB. We also discuss the possibilities of further improvement of the mixer performance.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0003-6951	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1610
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Author	Trifonov, V. A.; Karasik, B. S.; Zorin, M. A.; Gol’tsman, G. N.; Gershenzon, E. M.; Lindgren, M.; Danerud, M.; Winkler, D.
Title	9.6 μm wavelength mixing in a patterned YBa₂Cu₃O_7‐δ thin film			Type	Journal Article
Year	1996	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
Volume	68	Issue	10	Pages	1418-1420
Keywords	YBCO HTS HEB mixers
Abstract	Hot‐electron bolometric (HEB) mixing of 9.6 μm infrared radiation from two lasers in high‐quality YBa2Cu3O7−δ (YBCO) patterned thin film has been demonstrated. A heterodyne measurement showed an intermediate frequency (IF) bandwidth of 18 GHz, limited by our measurement system. An intrinsic limit of 100 GHz is predicted. Between 0.1 and 1 GHz intermediate frequency, temperature fluctuations with an equivalent output noise temperature Tfl up to ∼150 K, contributed to the mixer noise while Johnson noise dominated above 1 GHz. The overall conversion loss at 77 K at low intermediate frequencies was measured to be ∼25 dB, of which 13 dB was due to the coupling loss. The HEB mixer is very promising for use in heterodyne receivers within the whole infrared range.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0003-6951	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1613
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Author	Karasik, B. S.; Zorin, M. A.; Milostnaya, I. I.; Elantev, A. I.; Gol’tsman, G. N.; Gershenzon, E. M.
Title	Subnanosecond switching of YBaCuO films between superconducting and normal states induced by current pulse			Type	Journal Article
Year	1995	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
Volume	77	Issue	8	Pages	4064-4070
Keywords	YBCO HTS switches
Abstract	A study is reported of the current switching in high‐quality YBaCuO films deposited onto NdGaO3 and ZrO2 substrates between superconducting (S) and normal (N) states. The films 60–120 nm thick prepared by laser ablation were structured into single strips between gold contacts. The time dependence of the resistance after application of the voltage step to the film was monitored. Experiment performed within certain ranges of voltage amplitudes and temperatures has shown the occurrence of the fast stage (shorter than 400 ps) both in S‐N and N‐S transitions. A fraction of the film resistance changing within this stage in the S‐N transition increases with the current amplitude. A subnanosecond N‐S stage becomes more pronounced for shorter pulses. The fast switching is followed by the much slower change of resistance. The mechanism of switching is discussed in terms of the hot‐electron phenomena in YBaCuO. The contributions of other thermal processes (e.g., a phonon escape from the film, a heat diffusion in the film and substrate, a resistive domain formation) in the subsequent stage of the resistance dynamic have been also discussed. The basic limiting characteristics (average dissipated power, energy needed for switching, maximum repetition rate) of a picosecond switch which is proposed to be developed are estimated.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0021-8979	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1623
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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	Danerud, M.; Winkler, D.; Lindgren, M.; Zorin, M.; Trifonov, V.; Karasik, B. S.; Gol’tsman, G. N.; Gershenzon, E. M.
Title	Nonequilibrium and bolometric photoresponse in patterned YBa₂Cu₃O_7−δ thin films			Type	Journal Article
Year	1994	Publication	J. Appl. Phys.	Abbreviated Journal	J. Appl. Phys.
Volume	76	Issue	3	Pages	1902-1909
Keywords	YBCO HTS HEB detector, nonequilibrium response
Abstract	Epitaxial laser deposited YBa2Cu3O7−δ films of ∼50 nm thickness were patterned into detectors consisting of ten parallel 1 μm wide strips in order to study nonequilibrium and bolometric effects. Typically, the patterned samples had critical temperatures around 86 K, transition widths around 2 K and critical current densities above 1×106A/cm2 at 77 K. Pulsed laser measurements at 0.8 μm wavelength (17 ps full width at half maximum) showed a ∼30 ps response, attributed to electron heating, followed by a slower bolometric decay. Amplitude modulation in the band fmod=100 kHz–10 GHz of a laser with wavelength λ=0.8 μm showed two different thermal relaxations in the photoresponse. Phonon escape from the film (∼3 ns) is the limiting process, followed by heat diffusion in the substrate. Similar relaxations were also seen for λ=10.6 μm. The photoresponse measurements were made with the film in the resistive state and extended into the normal state. These states were created by supercritical bias currents. Measurements between 75 and 95 K (i.e., from below to above Tc) showed that the photoresponse was proportional to dR/dT for fmod=1 MHz and 4 GHz. The fast response is limited by the electron‐phonon scattering time, estimated to 1.8 ps from experimental data. The responsivity both at 0.8 and 10.6 μm wavelength was ∼1.2 V/W at fmod=1 GHz and the noise equivalent power was calculated to 1.5×10−9 WHz−1/2 for the fast response.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0021-8979	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1637
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Author	Karasik, B. S.; Zorin, M. A.; Milostnaya, I. I.; Elantev, A. I.; Gol’tsman, G. N.; Gershenzon, E. M.
Title	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	Lindgren, M.; Trifonov, V.; Zorin, M.; Danerud, M.; Winkler, D.; Karasik, B. S.; Gol’tsman, G. N.; Gershenzon, E.M.
Title	Transient resistive photoresponse of YBa₂Cu₃O_7−δ films using low power 0.8 and 10.6 μm laser radiation			Type	Journal Article
Year	1994	Publication	Appl. Phys. Lett.	Abbreviated Journal	Appl. Phys. Lett.
Volume	64	Issue	22	Pages	3036-3038
Keywords	YBCO HTS HEB, nonequilibrium
Abstract	Thin YBa2Cu3O7−δ laser deposited films were patterned into devices consisting of ten parallel 1 μm wide strips. Nonequilibrium picosecond and bolometric photoresponses were studied by the use of 17 ps full width at half‐maximum laser pulses and amplitude modulated radiation from an AlGaAs laser up to 10 GHz and from a CO2 laser up to 1 GHz. The time and frequency domain measurements were in agreement. The fast response can be explained by electron heating. The use of low optical power and a sensitive measurement system excluded any nonlinear transient processes and kinetic inductance changes in the superconducting state. At 1 GHz modulation frequency, the responsivity was ∼1.2 V/W both for 0.8 and 10.6 μm wavelengths. The sensitivity of a fast and spectrally broadband infrared detector is discussed.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0003-6951	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1639
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Author	Gol’tsman, G. N.; Kouminov, P. B.; Goghidze, I. G.; Karasik, B. S.; Gershenzon, E. M.
Title	Nonbolometric and fast bolometric responses of YBaCuO thin films in superconducting, resistive, and normal states			Type	Conference Article
Year	1994	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	2159	Issue		Pages	81-86
Keywords	YBCO HTS HEB, nonbolornetric
Abstract	The transient voltage response in both epitaxial and granular YBaCuO thin films to 20 ps pulses of YAG:Nd laser radiation with 0.63 micrometers and 1.54 micrometers was studied. In normal and resistive states both types of films demonstrate two components: nonequilibrium picosecond component and following bolometric nanosecond. The normalized amplitudes are almost the same for all films. In superconducting state we observed a kinetic inductive response and two-component shape after integration. The normalized amplitude of the response in granular films is up to several orders of magnitude larger than in epitaxial films. We interpret the nonequilibrium response in terms of a suppression of order parameter by the excess of quasiparticles followed by the change of resistance in normal and resistive states or kinetic inductance in superconducting state. The sharp rise of inductive response in granular films is explained both by a diminishing of the crossection for current percolation through the disordered network os Josephson weak links and by a decrease of condensate density in neighboring regions.
Address
Corporate Author				Thesis
Publisher	SPIE	Place of Publication		Editor	Nahum, M.; Villegier, J.-C.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	High-Temperature Superconducting Detectors: Bolometric and Nonbolometric
Notes				Approved	no
Call Number				Serial	1641
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Author	Gol’tsman, G. N.; Gershenzon, E. M.
Title	High speed hot-electron superconducting bolometer			Type	Conference Article
Year	1993	Publication	Proc. SPIE	Abbreviated Journal	Proc. SPIE
Volume	2104	Issue		Pages	181-182
Keywords	NbN HEb, Nb, Al
Abstract	Physical limitation of response time of a superconducting bolometer as well as the nature of non-equilibrium detection of radiation have been investigated for Al, Nb and NbN thin films in spectral range from submillimeter to near-infraredwavelengths [1,2]. In the case of ideal heat removal from the film with the f_‘. 100A thickness the detection mechanism is an electron heating effect that is not selective to radiation wavelength in a very broad range. The response time ofan electron heating bolometer is determined by an electron-phonon interaction time. This time is of about 10 ns, 0.5 ns and 20 ps for Al, Nb, and NbN correspondingly near the critical temperature of the superconducting film. Thesensitive area of the bolometer consists of a number of narrow strips (with awidth of 1Ã‚Âµm) connected in parallel to contact pads; these pads together witha sapphire substrate and a ground plate represent the microstrip transmissionline with an impedance of 50 Q.
Address
Corporate Author				Thesis
Publisher	SPIE	Place of Publication		Editor	Birch, J.R.; Parker, T.J.
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	18th International Conference on Infrared and Millimeter Waves
Notes				Approved	no
Call Number				Serial	1652
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