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Author Skalare, A.; McGrath, William R.; Echternach, P. M.; Leduc, H. G.; Siddiqi, I.; Verevkin, A.; Prober, D. E.
Title Aluminum hot-electron bolometer mixers at submillimeter wavelengths Type Journal Article
Year 2001 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal
Volume 11 Issue 1 Pages 641-644
Keywords (up) Al HEB mixer, contacts, interface, in situ, in-situ, Aluminium HEB mixer
Abstract Diffusion-cooled aluminum hot-electron bolometer (HEB) mixers are of interest for low-noise high resolution THz-frequency spectroscopy within astrophysics. Al HEB mixers offer operation with an order of magnitude less local oscillator power, higher intermediate frequency bandwidth and potentially lower noise than competing devices made from other materials. We report on mixer experiments at 618 GHz with devices fabricated from films with sheet resistances in the range from about 55 Ω down to about 9 Ω per square. Intermediate frequency bandwidths of up to 3 GHz were measured (1 μm long device), with absorbed local oscillator power levels of 0.5 to 6 nW and mixer conversion up to -21.5 dB. High input coupling efficiency implies that the electrons in the device are able to thermalize before escaping from the device. It was found that the long coherence length complicates mixer operations due to the proximity of the contact pads. Also, saturation at the IF frequency may be a concern for this type of device, and warrants further studies.
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ISSN 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number ref919426b Serial 1061
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Author Maslennikov, S. N.; Morozov, D. V.; Ozhegov, R. V.; Smirnov, K. V.; Okunev, O. V.; Gol’tsman, G. N.
Title Imaging system for submillimeter wave range based on AlGaAs/GaAs hot electron bolometer mixers Type Conference Article
Year 2004 Publication Proc. 5-th MSMW Abbreviated Journal Proc. 5-th MSMW
Volume 2 Issue Pages 558-560
Keywords (up) AlGaAs/GaAs HEB mixers
Abstract Electromagnetic radiation of the submillimeter (SMM) range is dispersed and absorbed significantly less than infrared (IR) radiation when passing through different objects. That is the reason for the development of an SMM imaging system. In this paper, we discuss the design of an SMM heterodyne imager, based on a matrix of AlGaAs/GaAs heterostructure hot electron bolometer mixers (HEB) with relatively high (about 77 K) operating temperature. The predicted double side band (DSB) noise temperature is about 1000 K and optimal local oscillator (LO) power is about 1 /spl mu/W for such mixers, which seems to be quite prospective for an SMM heterodyne imager.
Address Kharkov, Ukraine
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Area Expedition Conference The Fifth International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter, and Submillimeter Waves (IEEE Cat. No.04EX828)
Notes Approved no
Call Number Serial 1487
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Author Risacher, C.; Meledin, D.; Belitsky, V.; Bergman, P.
Title First 1.3 THz observations at the APEX telescope Type Conference Article
Year 2009 Publication Proc. 20th Int. Symp. Space Terahertz Technol. Abbreviated Journal
Volume Issue Pages 54-61
Keywords (up) balanced HEB mixer noise temperature APEX telescope stability Allan variance aperture efficiency
Abstract The Atacama Pathfinder EXperiment (APEX) 12m telescope is operating on the Llano Chajnantor, Chile, since 2003 and a set of state of the art sub-millimeter receivers have been installed for frequencies spanning from 150 GHz to 1500 GHz. In 2008, a balanced 1.3 THz Hot Electron Bolometer (HEB) receiver was installed for the atmospheric window 1250-1380 GHz. This instrument is part of a 4-channel receiver cryostat with the other channels being 211-275 GHz, 275-370 GHz and 380-500 GHz Sideband Separating (SSB) SIS receivers. This paper presents the first observations obtained so far with the 1.3 THz band during its first months of operation. The sky measurements were taken during opportunistic commissioning and science verification phases, when the weather conditions were sufficiently good with a Precipitable Water Vapor (PWV) below 0.25 mm, which was the case only a few nights during these months. We present the first observations of the molecular transition CO J=(11-10) line on different sources such as Orion-FIR4, CW-Leo and SgrB2(M). We describe the many challenges and difficulties encountered for achieving successful THz observations from a large sub-millimeter ground-based telescope.
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Call Number Serial 619
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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 (up) 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.
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Area Expedition Conference 24th European Microwave Conference
Notes Approved no
Call Number Serial 1635
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Author Maslennikov, S. N.; Finkel, M. I.; Antipov, S. V.; Polyakov, S. L.; Zhang, W.; Ozhegov, R.; Vachtomin, Yu. B.; Svechnikov, S. I.; Smirnov, K. V.; Korotetskaya, Yu. P.; Kaurova, N. S.; Gol'tsman, G. N.; Voronov, B. M.
Title Spiral antenna coupled and directly coupled NbN HEB mixers in the frequency range from 1 to 70 THz Type Conference Article
Year 2006 Publication Proc. 17th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 17th Int. Symp. Space Terahertz Technol.
Volume Issue Pages 177-179
Keywords (up) directly coupled NbN HEB mixers
Abstract We investigate both antenna coupled and directly coupled HEB mixers at several LO frequencies within the range of 2.5 THz to 70 THz. H20 (2.5+10.7 THz), and CO2 (30 THz) gas discharge lasers are used as the local oscillators. The noise temperature of antenna coupled mixers is measured at LO frequencies of 2.5 THz, 3.8 THz, and 30 THz. The results for both antenna coupled and directly coupled mixer types are compared. The devices with in—plane dimensions of 5x5 ,um 2 are pumped by LO radiation at 10.7 THz. The directly coupled HEB demonstrates nearly flat dependence of responsivity on frequency in the range of 25+64 THz.
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Publisher Place of Publication Paris, France Editor
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Notes Approved no
Call Number Serial 386
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Author Loudkov, D.; Tong, C. Y. E.; Blundell, R.; Kaurova, N.; Grishina, E.; Voronov, B.; Gol'tsman, G.
Title An investigation of the performance of the superconducting HEB슠mixer as a function of its RF슠embedding impedance Type Journal Article
Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal
Volume 15 Issue 2 Pages 472-475
Keywords (up) HEB mixer
Abstract
Address
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Publisher IEEE Place of Publication Editor
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Call Number Serial 371
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Author Gerecht, E.; Musante, C.F.; Zhuang, Y.; Ji, M.; Yngvesson, K.S.; Goyette, T.; Waldman, J.
Title NbN hot electron bolometric mixer with intrinsic receiver noise temperature of less than five times the quantum noise limit Type Conference Article
Year 2000 Publication Proc. IMS Abbreviated Journal
Volume 2 Issue Pages 1007-1010
Keywords (up) HEB mixer
Abstract In recent years, improvements in device development and quasi-optical coupling techniques utilizing planar antennas have led to a significant achievement in low noise receivers for the edges of the submillimeter frequency regime. Hot electron bolometric (HEB) receivers made of thin superconducting films such as NbN have produced a viable option for instruments designed to measure the molecular spectra for astronomical applications as well as in remote sensing of the atmosphere in the THz regime. This paper describes an NbN HEB mixer with intrinsic DSB receiver noise temperature of at most five times the quantum noise limit at frequencies as high as 2.24 THz
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Call Number Serial 477
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Author Ryabchun, Sergey; Tong, Cheuk-Yu Edward; Paine, Scott; Lobanov, Yury; Blundell, Raymond; Goltsman, Gregory
Title Temperature resolution of an HEB receiver at 810 GHz Type Journal Article
Year 2009 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 19 Issue 3 Pages 293-296
Keywords (up) HEB mixer
Abstract We present the results of direct measurements of the temperature resolution of an HEB receiver operating at 810 GHz, in both continuum and spectroscopic modes. In the continuum mode, the input of the receiver was switched between black bodies with different physical temperatures. With a system noise temperature of around 1100 K, the receiver was able to resolve loads which differed in temperature by about 1 K over an integration time of 5 seconds. This resolution is significantly worse than the value of 0.07 K given by the radiometer equation. In the spectroscopic mode, a gas cell filled with carbonyl sulphide (OCS) gas was used and the emission line at 813.3537060 GHz was measured using the receiver in conjunction with a digital spectrometer. From the observed spectra, we determined that the measurement uncertainty of the equivalent emission temperature was 2.8 K for an integration time of 0.25 seconds and a spectral resolution of 12 MHz, compared to a 1.4 K temperature resolution given by the radiometer equation. This relative improvement is due to the fact that at short integration times the contribution from 1/f noise and drift are less dominant. In both modes, the temperature resolution was improved by about 40% with the use of a feedback loop which adjusted the level of an injected microwave radiation to maintain a constant operating current of the HEB mixer. This stabilization scheme has proved to be very effective to keep the temperature resolution of the HEB receiver to close to the theoretical value given by the radiometer equation.
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Notes Approved no
Call Number Serial 636
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Author Масленникова, А. В.; Рябчун, С. А.; Финкель, М. И.; Каурова, Н. С.; Исупова, А. А.; Воронов, Б. М.; Гольцман, Г. Н.
Title Широкополосные смесители на горячих электронах на основе NbN наноструктур Type Journal Article
Year 2011 Publication Труды Московского физико-технического института Abbreviated Journal Труды МФТИ
Volume 3 Issue 2 Pages 31-34
Keywords (up) HEB mixer
Abstract Мы приводим данные исследования полосы преобразования смесителей на горячих электронах (hot-electron bolometer, НЕВ), изготовленных на основе тонких пленок NbN. Зависимость полосы преобразования от длины смесительного элемента находится в прекрасном согласии с результатами теоретической модели HEB-смесителя, в котором энергетическая релаксация электронов одновременно происходит по двум каналам: фононному и диффузионному.
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Notes Approved no
Call Number RPLAB @ gujma @ Serial 646
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Author Lobanov, Y. V.; Tong, Cheuk-Yu E.; Hedden, A. S.; Blundell, R.; Gol'tsman, G. N.
Title Microwave-assisted슠measurement슠of the슠frequency슠response슠of슠terahertz슠HEB슠mixers슠with a슠fourier슠transform슠spectrometer Type Conference Article
Year 2010 Publication 21st International Symposium on Space Terahertz Technology Abbreviated Journal 21st ISSTT
Volume Issue Pages 420-423
Keywords (up) HEB mixer
Abstract We describe a novel method of operation of the HEB direct detector for use with a Fourier Transform Spectrometer. Instead of elevating the bath temperature, we have measured the RF response of waveguide HEB mixers by applying microwave radiation to select appropriate bias conditions. In our experiment, a microwave signal is injected into the HEB mixer via its IF port. By choosing an appropriate injection level, the device can be operated close to the desired operating point. Furthermore, we have shown that both thermal biasing and microwave injection can reproduce the same spectral response of the HEB mixer. However, with the use of microwave injection, there is no need to wait for the mixer to reach thermal equilibrium, so characterisation can be done in less time. Also, the liquid helium consumption for our wet cryostat is also reduced. We have demonstrated that the signalto-noise ratio of the FTS measurements can be improved with microwave injection.
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Call Number RPLAB @ gujma @ Serial 725
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Author Maezawa, Hiroyuki
Title Application of superconducting hot-electron bolometer mixers for terahertz-band astronomy Type Journal Article
Year 2015 Publication IEICE Trans. Electronics Abbreviated Journal
Volume 98 Issue 3 Pages 196-206
Keywords (up) HEB mixer applications, HEB applications
Abstract Recently, a next-generation heterodyne mixer detector – a hot electron bolometer (HEB) mixer employing a superconducting microbridge – has gradually opened up terahertz-band astronomy. The surrounding state-of-the-art technologies including fabrication processes, 4 K cryostats, cryogenic low-noise amplifiers, local oscillator sources, micromachining techniques, and spectrometers, as well as the HEB mixers, have played a valuable role in the development of super-low-noise heterodyne spectroscopy systems for the terahertz band. The current developmental status of terahertz-band HEB mixer receivers and their applications for spectroscopy and astronomy with ground-based, airborne, and satellite telescopes are presented.
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Notes Approved no
Call Number Serial 1073
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Author de Lange, Gert; Krieg, Jean-Michel; Honingh, Netty; Karpov, Alexandre; Cherednichenko, Sergey
Title Performance of the HIFI flight mixers Type Conference Article
Year 2008 Publication Proc. 19th Int. Symp. Space Terahertz Technol. Abbreviated Journal
Volume Issue Pages 98-105
Keywords (up) HEB mixer applications, HEB applications
Abstract We summarize the technology and final results of the superconducting heterodyne SIS and HEB mixers that are developed for the HIFI instrument. Within HIFI 7 frequency bands cover the frequency range from 480 GHz to 1910 GHz. We describe the different device technologies and optical coupling schemes that are used to cover the frequency bands. The efforts of the different mixer teams that participate in HIFI have contributed to an instrument that will have unprecedented sensitivity and frequency coverage.
Address Groningen
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Notes Approved no
Call Number Serial 1074
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Author Bruderer, S.; Benz, A. O.; van Dishoeck, E. F.; Melchior, M.; Doty, S. D.; van der Tak, F.; Stäuber, P.; Wampfler, S. F.; Dedes, C.; Yıldız, U. A.; Pagani, L.; Giannini, T.; de Graauw, Th.; Whyborn, N.; Teyssier, D.; Jellema, W.; Shipman, R.; Schieder, R.; Honingh, N.; Caux, E.; Bächtold, W.; Csillaghy, A.; Monstein, C.; Bachiller, R.; Baudry, A.; Benedettini, M.; Bergin, E.; Bjerkeli, P.; Blake, G. A.; Bontemps, S.; Braine, J.; Caselli, P.; Cernicharo, J.; Codella, C.; Daniel, F.; di Giorgio, A. M.; Dominik, C.; Encrenaz, P.; Fich, M.; Fuente, A.; Goicoechea, J. R.; Helmich, F.; Herczeg, G. J.; Herpin, F.; Hogerheijde, M. R.; Jacq, T.; Johnstone, D.; Jørgensen, J. K.; Kristensen, L. E.; Larsson, B.; Lis, D.; Liseau, R.; Marseille, M.; McCoey, C.; Melnick, G.; Neufeld, D.; Nisini, B.; Olberg, M.; Parise, B.; Pearson, J. C.; Plume, R.; Risacher, C.; Santiago-García, J.; Saraceno, P.; Shipman, R.; Tafalla, M.; van Kempen, T. A.; Visser, R.; Wyrowski, F.
Title Herschel/HIFI detections of hydrides towards AFGL 2591. Envelope emission versus tenuous cloud absorption Type Journal Article
Year 2010 Publication Astron. Astrophys. Abbreviated Journal
Volume 521 Issue Pages L44 (1 to 7)
Keywords (up) HEB mixer applications, HIFI, Herschel
Abstract The Heterodyne Instrument for the Far Infrared (HIFI) onboard the Herschel Space Observatory allows the first observations of light diatomic molecules at high spectral resolution and in multiple transitions. Here, we report deep integrations using HIFI in different lines of hydrides towards the high-mass star forming region AFGL 2591. Detected are CH, CH+, NH, OH+, H2O+, while NH+ and SH+ have not been detected. All molecules except for CH and CH+ are seen in absorption with low excitation temperatures and at velocities different from the systemic velocity of the protostellar envelope. Surprisingly, the CH(JF,P = 3/22,- – 1/21,+ ) and CH+(J = 1–0, J = 2–1) lines are detected in emission at the systemic velocity. We can assign the absorption features to a foreground cloud and an outflow lobe, while the CH and CH+ emission stems from the envelope. The observed abundance and excitation of CH and CH+ can be explained in the scenario of FUV irradiated outflow walls, where a cavity etched out by the outflow allows protostellar FUV photons to irradiate and heat the envelope at larger distances driving the chemical reactions that produce these molecules.
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Notes Approved no
Call Number Serial 1083
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Author Benz, A. O.; Bruderer, S.; van Dishoeck, E. F.; Stäuber, P.; Wampfler, S. F.; Melchior, M.; Dedes, C.; Wyrowski, F.; Doty, S. D.; van der Tak, F.; Bächtold, W.; Csillaghy, A.; Megej, A.; Monstein, C.; Soldati, M.; Bachiller, R.; Baudry, A.; Benedettini, M.; Bergin, E.; Bjerkeli, P.; Blake, G. A.; Bontemps, S.; Braine, J.; Caselli, P.; Cernicharo, J.; Codella, C.; Daniel, F.; di Giorgio, A. M.; Dieleman, P.; Dominik, C.; Encrenaz, P.; Fich, M.; Fuente, A.; Giannini, T.; Goicoechea, J. R.; de Graauw, Th.; Helmich, F.; Herczeg, G. J.; Herpin, F.; Hogerheijde, M. R.; Jacq, T.; Jellema, W.; Johnstone, D.; Jørgensen, J. K.; Kristensen, L. E.; Larsson, B.; Lis, D.; Liseau, R.; Marseille, M.; McCoey, C.; Melnick, G.; Neufeld, D.; Nisini, B.; Olberg, M.; Ossenkopf, V.; Parise, B.; Pearson, J. C.; Plume, R.; Risacher, C.; Santiago-García, J.; Saraceno, P.; Schieder, R.; Shipman, R.; Stutzki, J.; Tafalla, M.; Tielens, A. G. G. M.; van Kempen, T. A.; Visser, R.; Yıldız, U. A.
Title Hydrides in young stellar objects: Radiation tracers in a protostar-disk-outflow system Type Journal Article
Year 2010 Publication Astron. Astrophys. Abbreviated Journal
Volume 521 Issue Pages L35 (1 to 5)
Keywords (up) HEB mixer applications, HIFI, Herschel
Abstract Context. Hydrides of the most abundant heavier elements are fundamental molecules in cosmic chemistry. Some of them trace gas irradiated by UV or X-rays.

Aims. We explore the abundances of major hydrides in W3 IRS5, a prototypical region of high-mass star formation.

Methods. W3 IRS5 was observed by HIFI on the Herschel Space Observatory with deep integration (2500 s) in 8 spectral regions.

Results. The target lines including CH, NH, H3O+, and the new molecules SH+, H2O+, and OH+ are detected. The H2O+ and OH+ J = 1–0 lines are found mostly in absorption, but also appear to exhibit weak emission (P-Cyg-like). Emission requires high density, thus originates most likely near the protostar. This is corroborated by the absence of line shifts relative to the young stellar object (YSO). In addition, H2O+ and OH+ also contain strong absorption components at a velocity shifted relative to W3 IRS5, which are attributed to foreground clouds.

Conclusions. The molecular column densities derived from observations correlate well with the predictions of a model that assumes the main emission region is in outflow walls, heated and irradiated by protostellar UV radiation.
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Call Number Serial 1082
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Author Bujarrabal, V.; Alcolea, J.; Soria-Ruiz, R.; Planesas, P.; Teyssier, D.; Marston, A. P.; Cernicharo, J.; Decin, L.; Dominik, C.; Justtanont, K.; de Koter, A.; Melnick, G.; Menten, K. M.; Neufeld, D. A.; Olofsson, H.; Schmidt, M.; Schöier, F. L.; Szczerba, R.; Waters, L. B. F. M.; Quintana-Lacaci, G.; Güsten, R.; Gallego, J. D.; Díez-González, M. C.; Barcia, A.; López-Fernández, I.; Wildeman, K.; Tielens, A. G. G. M.; Jacobs, K.
Title Herschel/HIFI observations of high-J CO transitions in the protoplanetary nebula CRL 618 Type Journal Article
Year 2010 Publication Astron. Astrophys. Abbreviated Journal
Volume 521 Issue Pages L3 (1 to 5)
Keywords (up) HEB mixer applications, HIFI, Herschel
Abstract Aims. We aim to study the physical conditions, particularly the excitation state, of the intermediate-temperature gas components in the protoplanetary nebula CRL 618. These components are particularly important for understanding the evolution of the nebula.

Methods. We performed Herschel/HIFI observations of several CO lines in the far-infrared/sub-mm in the protoplanetary nebula CRL 618. The high spectral resolution provided by HIFI allows measurement of the line profiles. Since the dynamics and structure of the nebula is well known from mm-wave interferometric maps, it is possible to identify the contributions of the different nebular components (fast bipolar outflows, double shells, compact slow shell) to the line profiles. The observation of these relatively high-energy transitions allows an accurate study of the excitation conditions in these components, particularly in the warm ones, which cannot be properly studied from the low-energy lines.

Results. The 12CO J = 16–15, 10–9, and 6–5 lines are easily detected in this source. Both 13CO J = 10–9 and 6–5 are also detected. Wide profiles showing spectacular line wings have been found, particularly in 12CO J = 16–15. Other lines observed simultaneously with CO are also shown. Our analysis of the CO high-J transitions, when compared with the existing models, confirms the very low expansion velocity of the central, dense component, which probably indicates that the shells ejected during the last AGB phases were driven by radiation pressure under a regime of maximum transfer of momentum. No contribution of the diffuse halo found from mm-wave data is identified in our spectra, because of its low temperature. We find that the fast bipolar outflow is quite hot, much hotter than previously estimated; for instance, gas flowing at 100 km s-1 must have a temperature higher than ~200 K. Probably, this very fast outflow, with a kinematic age <100 yr, has been accelerated by a shock and has not yet cooled down. The double empty shell found from mm-wave mapping must also be relatively hot, in agreement with the previous estimate.
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Notes Approved no
Call Number Serial 1084
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