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Author Cherednichenko, S.; Kollberg, E.; Angelov, I.; Drakinskiy, V.; Berg, T.; Merkel, H.
Title Effect of the direct detection effect on the HEB receiver sensitivity calibration Type Conference Article
Year 2005 Publication Proc. 16th Int. Symp. Space Terahertz Technol. Abbreviated Journal
Volume Issue Pages (up) 235-239
Keywords HEB, mixer, direct detection effect
Abstract We analyze the scale of the HEB receiver sensitivity calibration error caused by the so called “direct detection effect”. The effect comes from changing of the HEB parameters when whey face the calibration loads of different temperatures. We found that for HIFI Band 6 mixers (Herschel Space Observatory) the noise temperature error is of the order of 8% for 300K/77K loads (lab receiver) and 2.5% for 100K/10K loads (in HIFI). Using different approach we also predict that with an isolator between the mixer and the low noise amplifiers the error can be much smaller.
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Corporate Author Thesis
Publisher Place of Publication Göteborg, Sweden Editor
Language Summary Language Original Title
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ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 360
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Author Tong, C.-Y.E.; Meledin, D.V.; Marrone, D.P.; Paine, S.N.; Gibson, H.; Blundell, R.
Title Near field vector beam measurements at 1 THz Type Journal Article
Year 2003 Publication IEEE Microw. Compon. Lett. Abbreviated Journal
Volume 13 Issue 6 Pages (up) 235-237
Keywords HEB, mixer, waveguide, LO power, local oscillator power, saturation effect, dynamic range
Abstract We have performed near-field vector beam measurements at 1.03 THz to characterize and align the receiver optics of a superconducting receiver. The signal source is a harmonic generator mounted on an X-Y translation stage. We model the measured two-dimensional complex beam pattern by a fundamental Gaussian mode, from which we derive the position of the beam center, the beam radius and the direction of propagation. By performing scans in the planes separated by 400 mm, we have confirmed that our beam pattern measurements are highly reliable.
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1531-1309 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ lobanovyury @ Serial 574
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Author Vachtomin, Y. B.; Antipov, S. V.; Maslennikov, S. N.; Smirnov, K. V.; Polyakov, S. L.; Kaurova, N. S.; Grishina, E. V.; Voronov, B. M.; Gol'tsman, G. N.
Title Noise temperature measurements of NbN phonon-cooled hot electron bolometer mixer at 2.5 and 3.8 THz Type Conference Article
Year 2004 Publication Proc. 15th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 15th Int. Symp. Space Terahertz Technol.
Volume Issue Pages (up) 236-241
Keywords HEB mixer, NbN, direct detection effect
Abstract We present the results of noise temperature measurements of NbN phonon-cooled HEB mixers based on a 3.5 nm NbN film deposited on a high-resistivity Si substrate with a 200 nm – thick MgO buffer layer. The mixer element was integrated with a log-periodic spiral antenna. The noise temperature measurements were performed at 2.5 THz and at 3.8 THz local oscillator frequencies for the 3 µm x 0.2 µm active area devices. The best uncorrected receiver noise temperatures found for these frequencies are 1300 K and 3100 K, respectively. A water vapour discharge laser was used as the LO source. We also present the results of direct detection contribution to the measured Y-factor and of a possible error of noise temperature calculation. This error was more than 8% for the mixer with in-plane dimensions of 2.4 x 0.16 µm 2 at the optimal noise temperature point. The use of a mesh filter enabled us to avoid the effect of direct detection and decrease optical losses by 0.5 dB. The paper is concluded by the investigation results of the mixer polarization response. It was shown that the polarization can differ from the circular one at 3.8 THz by more than 2 dB.
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Corporate Author Thesis
Publisher Place of Publication Northampton, Massachusetts, USA Editor
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Notes Approved no
Call Number Serial 344
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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. 10th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 10th Int. Symp. Space Terahertz Technol.
Volume Issue Pages (up) 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.
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Notes Approved no
Call Number Serial 1575
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Author Semenov, Alexei D.; Richter, Heiko; Hubers, Heinz-Wilhelm; Gunther, Burghardt.; Smirnov, Andrey; Il'in, Konstantin S.; Siegel, Michael; Karamarkovic, Jugoslav P.
Title Terahertz performance of integrated lens antennas with a hot-electron bolometer Type Journal Article
Year 2007 Publication IEEE Trans. Microw. Theory Techn. Abbreviated Journal
Volume 55 Issue 2 Pages (up) 239-247
Keywords HEB, lens antenna
Abstract
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9480 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 538
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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 (up) 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.
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Notes Approved no
Call Number Serial 1506
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Author Antipov, S. V.; Svechnikov, S. I.; Smirnov, K. V.; Vakhtomin, Y. B.; Finkel, M. I.; Goltsman, G. N.; Gershenzon, E. M.
Title Noise temperature of quasioptical NbN hot electron bolometer mixers at 900 GHz Type Journal Article
Year 2001 Publication Physics of Vibrations Abbreviated Journal Physics of Vibrations
Volume 9 Issue 4 Pages (up) 242-245
Keywords NbN HEB mixers
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1069-1227 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1550
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Author Kroug, M.; Cherednichenko, S.; Choumas, M.; Merkel, H.; Kollberg, E.; Hübers, H.-W.; Richter, H.; Loudkov, D.; Voronov, B.; Gol'Tsman, G.
Title HEB quasi-optical heterodyne receiver for THz frequencies Type Conference Article
Year 2001 Publication Proc. 12th Int. Symp. Space Terahertz Technol. Abbreviated Journal
Volume Issue Pages (up) 244-252
Keywords HEB mixer, NbN, MgO, conversion gain bandwidth, noise temperature
Abstract
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Corporate Author Thesis
Publisher Place of Publication San Diego, CA, USA Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
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Notes Approved no
Call Number Serial 319
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Author Cherednichenko, S.; Yagoubov, P.; Il'In, K.; Gol'tsman, G.; Gershenzon, E.
Title Large bandwidth of NbN phonon-cooled hot-electron bolometer mixers on sapphire substrates Type Conference Article
Year 1997 Publication Proc. 8th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 8th Int. Symp. Space Terahertz Technol.
Volume Issue Pages (up) 245-257
Keywords NbN HEB mixers, fabrication process
Abstract The bandwidth of NbN phonon-cooled hot electron bolometer mixers has been systematically investigated with respect to the film thickness and film quality variation. The films, 2.5 to 10 mm thick, were fabricated on sapphire substrates using DC reactive magnetron sputtering. All devices consisted of several parallel strips, each 1 1.1 wide and 211 long, placed between Ti-Au contact pads. To measure the gain bandwidth we used two identical BWOs operating in the 120-140 GHz frequency range, one functioning as a local oscillator and the other as a signal source. The majority of the measurements were made at an ambient temperature of 4.5 K with optimal LO and DC bias. The maximum 3 dB bandwidth (about 4 GHz) was achieved for the devices made of films which were 2.5-3.5 nm thick, had a high critical temperature, and high critical current density. A theoretical analysis of bandwidth for these mixers based on the two-temperature model gives a good description of the experimental results if one assumes that the electron temperature is equal to the critical temperature.
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Notes Approved no
Call Number Serial 276
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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. 6th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 6th Int. Symp. Space Terahertz Technol.
Volume Issue Pages (up) 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.
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Notes Approved no
Call Number Serial 1625
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