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Author |
Maezawa, Hiroyuki |
Title |
Application of superconducting hot-electron bolometer mixers for terahertz-band astronomy |
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Journal Article |
Year |
2015 |
Publication |
IEICE Trans. Electronics |
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98 |
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3 |
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196-206 |
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HEB mixer applications, HEB applications |
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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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1073 |
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Tretyakov, I. V.; Ryabchun, S. A.; Maslennikov, S. N.; Finkel, M. I.; Kaurova, N. S.; Seleznev, V. A.; Voronov, B. M.; Gol'tsman, G.N. |
Title |
NbN HEB mixer: fabrication, noise temperature reduction and characterization |
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Conference Article |
Year |
2008 |
Publication |
Proc. Basic problems of superconductivity |
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HEB, mixer, noise temperature, conversion gain bandwidth |
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We demonstrate that in the terahertz region superconducting hot-electron mixers offer the lowest noise temperature, opening the possibility of using HTS's in the future to fabricate these devices. Specifically, a noise temperature of 950 K was measured for the receiver operating at 2.5 THz with a NbN HEB mixer, and a gain bandwidth of 6 GHz was measured at 300 GHz near Tc for the same mixer. |
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Moscow-Zvenigorod |
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591 |
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Финкель, М. И. |
Title |
Терагерцовые смесители на эффекте электронного разогрева в ультратонких плёнках NbN и NbTiN |
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Manuscript |
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2006 |
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М. МПГУ |
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HEB, detector, mixer, terahertz, THz, infrared, IR, direct detection effect, conversion bandwidth, conversion loss |
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Ph.D. thesis |
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597 |
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Рябчун, С. А. |
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Широкополосные высокостабильные терагерцовые смесители на горячих электронах из тонких сверхпроводниковых пленок NbN |
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Manuscript |
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2009 |
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М. МПГУ |
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98 |
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HEB, mixer, terahertz, THz, stability, Allan variance, conversion bandwidth, in-situ technique, Au contacts |
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Ph.D. thesis |
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598 |
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Ryabchun, S. A.; Tretyakov, I. V.; Pentin, I. V.; Kaurova, N. S.; Seleznev, V. A.; Voronov, B. M.; Finkel, M. I.; Maslennikov, S. N.; Gol'tsman, G. N. |
Title |
Low-noise wide-band hot-electron bolometer mixer based on an NbN film |
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Journal Article |
Year |
2009 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal ![sorted by Abbreviated Journal field, descending order (down)](img/sort_desc.gif) |
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52 |
Issue |
8 |
Pages |
576-582 |
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HEB mixer, in-situ contacts, noise temperature, conversion gain bandwidth, diffusion cooling channel |
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We develop and study a hot-electron bolometer mixer made of a two-layer NbN–Au film in situ deposited on a silicon substrate. The double-sideband noise temperature of the mixer is 750 K at a frequency of 2.5 THz. The conversion efficiency measurements show that at the superconducting transition temperature, the intermediate-frequency bandwidth amounts to about 6.5 GHz for a mixer 0.112 μm long. These record-breaking characteristics are attributed to the improved contacts between a sensitive element and a helical antenna and are reached due to using the in situ deposition of NbN and Au layers at certain stages of the process. |
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599 |
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Рябчун, С. А.; Третьяков, И. В.; Пентин, И. В; Каурова, Н. С.; Селезнев, В. А; Воронов, Б. М.; Финкель, М. И.; Масленников, С. Н.; Гольцман, Г. Н. |
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Малошумящий широкополосный терагерцовый смеситель на эффекте электронного разогрева в плёнке NbN |
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Journal Article |
Year |
2009 |
Publication |
Известия высших учебных заведений. Радиофизика |
Abbreviated Journal ![sorted by Abbreviated Journal field, descending order (down)](img/sort_desc.gif) |
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52 |
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8 |
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641-648 |
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HEB mixer, in-situ contacts, noise temperature, conversion gain bandwidth, diffusion cooling channel |
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Разработан и исследован смеситель на горячих электронах, изготовленный из двуслойной плёнки NbN-Au, осаждённой на кремневую подложку in situ. Двухполосная шумовая температура устройства составила 750 К на частоте 2.5 ТГц. Измерения эффективности преобразования для смесителя длиной 0.112 мкм вблизи температуры сверхпроводящего перехода показали полосу промежуточных частот около 6.5 ГГц. Эти результаты являются рекордными и были получены за счёт улучшения контактов между чувствительным элементом и спиральной антенной при замене технологического маршрута с нанесением слоёв NbN и Au в отдельных процессах на технологический процесс, в котором данные слои наносятся in situ без нарушения вакуума. |
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600 |
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Nebosis, R. S.; Semenov, A. D.; Gousev, Yu. P.; Renk, K. F. |
Title |
Rigorous analysis of a superconducting hot-electron bolometer mixer: theory and comparision with experiment |
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Conference Article |
Year |
1996 |
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Proc. 7th Int. Symp. Space Terahertz Technol. |
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601-613 |
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HEB mixer, model, conversion gain, noise temperature, impedance, 2.5 THz |
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Charlottesville, Virginia, USA |
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605 |
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Risacher, C.; Meledin, D.; Belitsky, V.; Bergman, P. |
Title |
First 1.3 THz observations at the APEX telescope |
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Conference Article |
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2009 |
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Proc. 20th Int. Symp. Space Terahertz Technol. |
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54-61 |
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balanced HEB mixer noise temperature APEX telescope stability Allan variance aperture efficiency |
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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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619 |
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Karasik, Boris S.; Cantor, Robin |
Title |
Optical NEP in hot-electron nanobolometers |
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Journal Article |
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2010 |
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1-7 |
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HEB, Ti, NEP, femtowatt, SAFARI, SPICA, 650 GHz, 0.65 THz, 460 um, twin slot antenna, SQUID readout |
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For the first time, we have measured the optical noise equivalent power (NEP) in titanium (Ti) superconducting hot-electron nanobolometers (nano-HEBs). The bolometers were 2{\mu}mx1{\mu}mx20nm and 1{\mu}mx1{\mu}mx20nm planar antenna-coupled devices. The measurements were done at {\lambda} = 460 {\mu}m using a cryogenic black body radiation source delivering optical power from a fraction of a femtowatt to a few 100s of femtowatts. A record low NEP = 3x10^{-19} W/Hz^{1/2} at 50 mK has been achieved. This sensitivity meets the requirements for SAFARI instrument on the SPICA telescope. The ways for further improvement of the nano-HEB detector sensitivity are discussed. |
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To appear in Proc. 21st Int. Symp. on Spc. THz Technol., Oxford, UK, 23-25 March, 2010 |
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623 |
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Huebers, Heinz-Wilhelm; Pavlov, S.; Semenov, A.; Köhler, R.; Mahler, L.; Tredicucci, A.; Beere, H.; Ritchie, D.; Linfield, E. |
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Terahertz quantum cascade laser as local oscillator in a heterodyne receiver |
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2005 |
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Optics Express |
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13 |
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15 |
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5890-5896 |
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QCL heterodyne, 6 mW at 2.5 THz, HEB mixer, terahertz |
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Terahertz quantum cascade lasers have been investigated with respect to their performance as a local oscillator in a heterodyne receiver. The beam profile has been measured and transformed in to a close to Gaussian profile resulting in a good matching between the field patterns of the quantum cascade laser and the antenna of a superconducting hot electron bolometric mixer. Noise temperature measurements with the hot electron bolometer and a 2.5 THz quantum cascade laser yielded the same result as with a gas laser as local oscillator. |
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627 |
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Rabanus, D.; Graf, U. U.; Philipp, M.; Ricken, O.; Stutzki, J.; Vowinkel, B.; Wiedner, M. C.; Walther, C.; Fischer, M.; Faist, J. |
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Phase locking of a 1.5 terahertz quantum cascade laser and use as a local oscillator in a heterodyne HEB receiver |
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Journal Article |
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2009 |
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Optics Express |
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17 |
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3 |
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1159-1168 |
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QCL heterodyne, 300 uW at 1.5 THz, HEB mixer |
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We demonstrate for the first time the closure of an electronic phase lock loop for a continuous–wave quantum cascade laser (QCL) at 1.5 THz. The QCL is operated in a closed cycle cryo cooler. We achieved a frequency stability of better than 100 Hz, limited by the resolution bandwidth of the spectrum analyser. The PLL electronics make use of the intermediate frequency (IF) obtained from a hot electron bolometer (HEB) which is downconverted to a PLL IF of 125 MHz. The coarse selection of the longitudinal mode and the fine tuning is achieved via the bias voltage of the QCL. Within a QCL cavity mode, the free-running QCL shows frequency fluctuations of about 5 MHz, which the PLL circuit is able to control via the Stark–shift of the QCL gain material. Temperature dependent tuning is shown to be nonlinear, and of the order of -16 MHz/K. Additionally we have used the QCL as local oscillator (LO) to pump an HEB and perform, again for the first time at 1.5 THz, a heterodyne experiment, and obtain a receiver noise temperature of 1741 K. |
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628 |
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de Lange, Gert; Krieg, Jean-Michel; Honingh, Netty; Karpov, Alexandre; Cherednichenko, Sergey |
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Performance of the HIFI flight mixers |
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Conference Article |
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2008 |
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Proc. 19th Int. Symp. Space Terahertz Technol. |
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98-105 |
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HEB mixer applications, HEB applications |
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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. |
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Groningen |
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1074 |
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Tretyakov, Ivan; Ryabchun, Sergey; Finkel, Matvey; Maslennikov, Sergey; Maslennikova, Anna; Kaurova, Natalia; Lobastova, Anastasia; Voronov, Boris; Gol'tsman, Gregory |
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Ultrawide noise bandwidth of NbN hot-electron bolometer mixers with in situ gold contacts |
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2011 |
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IEEE Trans. Appl. Supercond. |
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21 |
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3 |
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620-623 |
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NbN HEB mixer bandwidth |
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We report a noise bandwidth of 7 GHz in the new generation of NbN hot-electron bolometer (HEB) mixers that are being developed for the space observatory Millimetron. The HEB receiver driven by a 2.5-THz local oscillator offered a noise temperature of 600 K in a 50-MHz final detection bandwidth. As the filter center frequency was swept this value remained nearly constant up to the cutoff frequency of the cryogenic amplifier at 7 GHz. We believe that such a low value of the noise temperature is due to reduced radio frequency (RF) loss at the interface between the superconducting film and the gold contacts. We have also performed gain bandwidth measurements at the superconducting transition on HEB mixers with various lengths and found them to be in excellent agreement with the results of the analytical and numerical models developed for the HEB mixer with both diffusion and phonon cooling of hot electrons. |
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RPLAB @ gujma @ |
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716 |
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Lobanov, Y.; Tong, E.; Blundell, R.; Hedden, A.; Voronov, B.; Gol'tsman, G. |
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Large-signal frequency response of an HEB mixer: from 300 MHz to terahertz |
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2011 |
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IEEE Trans. Appl. Supercond. |
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21 |
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3 |
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628-631 |
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waveguide NbN HEB mixers |
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We present a study of the large signal frequency response of an HEB mixer over a wide frequency range. In our experiments, we have subjected the HEB mixer to incident electromagnetic radiation from 0.3 GHz to 1 THz. The mixer element is an NbN film deposited on crystalline quartz. The mixer chip is mounted in a waveguide cavity, coupled to free space with a diagonal horn. At microwave frequencies, electromagnetic radiation is applied through the coaxial bias port of the mixer block. At higher frequencies the input signal passes via the diagonal horn feed. At each frequency, the incident power is varied and a family of I-V curves is recorded. From the curves we identify 3 distinct regimes of operation of the mixer separated by the phonon relaxation frequency and the superconducting energy gap frequency observed at about 3 GHz and 660 GHz respectively. In this paper, we will present observed curves and discuss the results of our experiment. |
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Ожегов, Роман Викторович |
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Флуктуационная чувствительность и стабильность приемников с СИС и HEB смесителями для терагерцового тепловидения |
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2011 |
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Радиофизика |
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135 |
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HEB |
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no |
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RPLAB @ gujma @ |
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731 |
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