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Author | Maslennikov, S. N.; Morozov, D. V.; Ozhegov, R. V.; Smirnov, K. V.; Okunev, O. V.; Gol’tsman, G. N. | ||||
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Imaging system for submillimeter wave range based on AlGaAs/GaAs hot electron bolometer mixers | Type | Conference Article | ||
Year | 2004 | Publication | Proc. 5-th MSMW | Abbreviated Journal | Proc. 5-th MSMW |
Volume | 2 | Issue | Pages | 558-560 | |
Keywords | AlGaAs/GaAs HEB mixers | ||||
Abstract | Electromagnetic radiation of the submillimeter (SMM) range is dispersed and absorbed significantly less than infrared (IR) radiation when passing through different objects. That is the reason for the development of an SMM imaging system. In this paper, we discuss the design of an SMM heterodyne imager, based on a matrix of AlGaAs/GaAs heterostructure hot electron bolometer mixers (HEB) with relatively high (about 77 K) operating temperature. The predicted double side band (DSB) noise temperature is about 1000 K and optimal local oscillator (LO) power is about 1 /spl mu/W for such mixers, which seems to be quite prospective for an SMM heterodyne imager. | ||||
Address | Kharkov, Ukraine | ||||
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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 | Baubert, J.; Salez, M.; Merkel, H.; Pons, P.; Cherednichenko, S.; Lecomte, B.; Drakinsky, V.; Goltsman, G.; Leone, B. | ||||
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IF gain bandwidth of membrane-based NbN hot electron bolometers for SHAHIRA | Type | Journal Article | ||
Year | 2005 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 15 | Issue | 2 | Pages | 507-510 |
Keywords | NbN HEB mixers, applications | ||||
Abstract | SHAHIRA (Submm Heterodyne Array for HIgh-speed Radio Astronomy) is a project supported by the European Space Agency (ESA) and is designed to fly on the SOFIA observatory. A quasi-optic design has been chosen for 2.5/2.7 THz and 4.7 THz, for hydroxyde radical OH, deuterated hydrogen HD and neutral atomic oxygen OI lines observations. Hot electron bolometers (HEBs) have been processed on 1 /spl mu/m thick SiO/sub 2//Si/sub 3/N/sub 4/ stress-less membranes. In this paper we analyse the intermediate frequency (IF) gain bandwidth from the theoretical point of view, and compare it to measurements. | ||||
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ISSN | 1558-2515 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1468 | |||
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Author | Cao, Aiqin; Jiang, L.; Chen, S.H.; Antipov, S.V.; Shi, S.C. | ||||
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IF gain bandwidth of a quasi-optical NbN superconducting HEB mixer | Type | Conference Article | ||
Year | 2007 | Publication | Proc. International conference on microwave and millimeter wave technology | Abbreviated Journal | Proc. ICMMT |
Volume | Issue | Pages | 1-3 | ||
Keywords | HEB, mixer, gain bandwidth | ||||
Abstract | In this paper, the intermediate frequency (IF) gain bandwidth of a quasi-optical NbN superconducting hot-electron bolometer (HEB) mixer is investigated at 500 GHz with an IF system incorporating with a frequency down-converting scheme which is able to sweep the IF signal in a frequency range of 0.3-4 GHz. The IF gain bandwidth of the device is measured to be 1.5 GHz when it is biased at a voltage of the minimum noise temperature, and becomes larger when the bias voltage increases. | ||||
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Publisher | Place of Publication | Builin | Editor | ||
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Notes | Approved | no | |||
Call Number | RPLAB @ lobanovyury @ | Serial | 575 | ||
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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. 11th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 11th 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. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1557 | |||
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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. | ||||
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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 | 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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Notes | Approved | no | |||
Call Number | Serial | 1082 | |||
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