Records |
Author |
Cherednichenko, S.; Khosropanah, P.; Berg, T.; Merkel, H.; Kollberg, E.; Drakinskiy, V.; Voronov, B.; Gol’tsman, G. |
Title |
Optimization of HEB mixer for the Herschel Space Observatory |
Type |
Abstract |
Year |
2004 |
Publication |
Proc. 15th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 15th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
16 |
Keywords |
NbN HEB mixers, applications |
Abstract |
A mixer development for the HIFI instrument of the Herschel Space Observatory has come to the final stage. In our paper and conference presentation we will describe the most important details of the Band 6 Low and High Mixer Unit design. Special attention will be given to the optimization of the hot- electron bolometer mixer chip, which is based on 3.5nm NbN superconducting film on silicon. As the HEB’s local oscillator power requirements depend on the bolometer size, we have compared mixer noise temperature for different bolometer width- to- length ratio. A trade- off between mixer performance and local oscillator power requirements results in the mixer units equipped with optimized mixer chips, providing the largest coverage of the Band6 RF band with the lowest possible receiver noise. A short account of the beam pattern measurements of Band6 mixers will be given as well. |
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1490 |
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Cherednichenko, S.; Kroug, M.; Khosropanah, P.; Adam, A.; Merkel, H.; Kolberg, E.; Loudkov, D.; Voronov, B.; Gol'tsman, G.; Richter, H.; Hübers, H. W. |
Title |
A broadband terahertz heterodyne receiver with an NbN HEB mixer |
Type |
Conference Article |
Year |
2002 |
Publication |
Proc. 13th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 13th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
85-95 |
Keywords |
NbN HEB mixers |
Abstract |
We present a broadband and low noise heterodyne receiver for 1.4-1.7 THz designed for the Hershel Space Observatory. A phonon- cooled NbN HEB mixer was integrated with a normal metal double- slot antenna and an elliptical silicon lens. DSB receiver noise temperature Tr was measured from 1 GHz through 8GHz intermediate frequency band with 50 MHz instantaneous bandwidth. At 4.2 K bath temperature and at 1.6 THz LO frequency Tr is 800 K with the receiver noise bandwidth of 5 GHz. While at 2 K bath temperature Tr was as low as 700 K. At 0.6 THz and 1.1 THz a spiral antenna integrated NbN HEB mixer showed the receiver noise temperature 500 K and 800 K, though no antireflection coating was used in this case. Tr of 1100 K was achieved at 2.5 THz while the receiver noise bandwidth was 4 GHz. |
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Cambridge, MA, USA |
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Harward University |
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332 |
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Author |
Loudkov, D.; Khosropanah, P.; Cherednichenko, S.; Adam, A.; MerkeI, H.; Kollberg, E.; Gol'tsman, G. |
Title |
Broadband fourier transform spectrometer (FTS) measurements of spiral and double-slot planar antennas at THz frequencies |
Type |
Conference Article |
Year |
2002 |
Publication |
Proc. 13th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 13th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
373-369 |
Keywords |
NbN HEB mixers |
Abstract |
The direct responses of NbN phonon-cooled hot electron bolometer (HEB) mixers, integrated with different planar antennas, are measured, using Fourier Transform Spectrometer (F1S). One spiral antenna and several double slot antennas, designed for 0.6, 1.4, 1.6, 1.8 and 2.5 THz central frequencies, are investigated. The Optimization of the measurement set-up is discussed in terms of the beam splitter and the F11S-to-HEB coupling. The result shows that the spiral antenna is circular polarized and has a bandwidth of about 2 THz. The frequency bands of double slot antennas show some shift from the design values and their relative bandwidth increases by increasing the design frequency. The antenna responses do not depend on the HEB bias point and temperature, as long as the device is in the resistive state. |
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no |
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Serial |
1530 |
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Author |
Cherednichenko, S.; Kroug, M.; Merkel, H.; Kollberg, E.; Loudkov, D.; Smirnov, K.; Voronov, B.; Gol'tsman, G.; Gershenzon, E. |
Title |
Local oscillator power requirement and saturation effects in NbN HEB mixers |
Type |
Conference Article |
Year |
2001 |
Publication |
Proc. 12th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 12th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
273-285 |
Keywords |
NbN HEB mixers, LO power, local oscillator power, saturation effect, dynamic range |
Abstract |
The local oscillator power required for NbN hot-electron bolometric mixers (P LO ) was investigated with respect to mixer size, critical temperature and ambient temperature. P LO can be decreased by a factor of 10 as the mixer size decreases from 4×0.4 µm 2 to 0.6×0.13 µm 2 . For the smallest volume mixer the optimal local oscillator power was found to be 15 nW. We found that for such mixer no signal compression was observed up to an input signal of 2 nW which corresponds to an equivalent input load of 20,000 K. For a constant mixer volume, reduction of T c can decrease optimal local oscillator power at least by a factor of 2 without a deterioration of the receiver noise temperature. Bath temperature was found to have minor effect on the receiver characteristics. |
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San Diego, CA, USA |
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Jet Propulsion Laboratory, California Inst.it.u.t.e of Technology |
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318 |
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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 |
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Conference Article |
Year |
2001 |
Publication |
Proc. 12th Int. Symp. Space Terahertz Technol. |
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Volume |
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Issue |
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Pages |
244-252 |
Keywords |
HEB mixer, NbN, MgO, conversion gain bandwidth, noise temperature |
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Place of Publication |
San Diego, CA, USA |
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319 |
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Author |
Merkel, H. F.; Khosropanah, P.; Sigfrid Yngvesson, K.; Cherednichenko, S.; Kroug, M.; Adam, A.; Kollberg, E. |
Title |
An active zone small signal model for hot-electron bolometric mixers |
Type |
Conference Article |
Year |
2001 |
Publication |
Proc. 12th Int. Symp. Space Terahertz Technol. |
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Volume |
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Issue |
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Pages |
55 |
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Place of Publication |
San Diego, CA, USA |
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RPLAB @ s @ losses_in_contacts_merkel |
Serial |
320 |
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Author |
Khosropanah, P.; Merkel, H.; Yngvesson, S.; Adam, A.; Cherednichenko, S.; Kollberg, E. |
Title |
A distributed device model for phonon-cooled HEB mixers predicting IV characteristics, gain, noise and IF bandwidth |
Type |
Conference Article |
Year |
2000 |
Publication |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
474-488 |
Keywords |
HEB mixer numerical model, diffusion cooling channel, diffusion channel, distributed HEB model, distributed model |
Abstract |
A distributed model for phonon-cooled superconductor hot electron bolometer (HEB) mixers is given, which is based on solving the one-dimensional heat balance equation for the electron temperature profile along the superconductor strip. In this model it is assumed that the LO power is absorbed uniformly along the bridge but the DC power absorption depends on the local resistivity and is thus not uniform. The electron temperature dependence of the resistivity is assumed to be continuous and has a Fermi form. These assumptions are used in setting up the non-linear heat balance equation, which is solved numerically for the electron temperature profile along the bolometer strip. Based on this profile the resistance of the device and the IV curves are calculated. The IV curves are in excellent agreement with measurement results. Using a small signal model the conversion gain of the mixer is obtained. The expressions for Johnson noise and thermal fluctuation noise are derived. The calculated results are in close agreement with measurements, provided that one of the parameters used is adjusted. |
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University of Michigan, Ann Arbor, MI USA |
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Serial |
893 |
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Author |
Cherednichenko, S.; Rönnung, F.; Gol’tsman, G.; Kollberg, E.; Winkler, D. |
Title |
YBa2Cu3O7-δ hot-electron bolometer mixer at 0.6 THz |
Type |
Conference Article |
Year |
2000 |
Publication |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
517-522 |
Keywords |
YBCO HTS HEB mixers |
Abstract |
We present an investigation of hot-electron bolometric mixer based on a YBa 2 Cu 3 O 7-δ (YBCO) superconducting thin film. Mixer conversion loss of –46 dB, absorbed local oscillator power and intermediate frequency bandwidth were measured at the local oscillator frequency 0.6 THz. The fabrication technique for nanoscale YBCO hot-electron bolometer (HEB) mixer integrated with a planar antenna structure is described. |
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no |
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Serial |
1556 |
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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 |
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Issue |
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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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no |
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1557 |
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Author |
Cherednichenko, S.; Ronnung, F.; Gol'tsman, G.; Gershenzon, E.; Winkler, D. |
Title |
YBa2Cu3O7-δ hot-electron bolometer with submicron dimensions |
Type |
Conference Article |
Year |
1999 |
Publication |
Proc. 10th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 10th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
181-189 |
Keywords |
YBCO HTS HEB mixers |
Abstract |
Photoresponse of YBa2Cu3O7-δ hot-electron bolometers to modulated near-infrared radiation was studied at a modulation .frequenc y var y ing from 0.2 MHz to 2 GHz. Bolometers were _fabricated from a 50 12 M thick film and had in-plane areas of 10x10 , um 2 . 2x0.2 s um', 1x0.2 p.m', and 0.5x0.2 jim. We found that nonequilibrium phonons cool down more effectively for the bolometers with smaller area. For the smallest bolometer the bolometric component in the response is 10 dB less than for the largest one. |
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no |
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Serial |
1572 |
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Author |
Schwaab, G. W.; Hübers, H.-W.; Schubert, J.; Erichsen, Patrik; Gol'tsman, G.; Semenov, A.; Verevkin, A.; Cherednichenko, S.; Gershenzon, E. |
Title |
A high resolution spectrometer for the investigation of molecular structures in the THZ range |
Type |
Conference Article |
Year |
1999 |
Publication |
Proc. 10th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 10th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
530-538 |
Keywords |
antireflection coatings, dielectric mirrors |
Abstract |
A status report on the design study of a novel tunable far-infrared (TuFTR) spectrometer for the investigation of the structure of weakly bound molecular complexes is given. The goal is a sensitive TuFIR spectrometer with full frequency coverage from 1-6 THz. To hit the goal, advanced sources (e.g. p-Ge lasers) and detectors (e.g. superconducting hot electron bolometric (HEB) mixers) shall be employed to extend the technique of cavity ringdown spectroscopy, that is currently used at optical and infrared frequencies to the FIR spectral range. Critical for such a system are high-Q resonators that still allow good optical coupling, and wideband antireflection coatings to increase detector sensitivity and decrease optical path losses. 2 nd order effective media theory and an iterative multilayer algorithm have been employed to design wideband antireflection coatings for dielectrics with large dielectric constants like Ge or Si. Taking into account 6 layers, for Si bandwidths of 100% of the center frequency could be obtained with power reflectivities below 1% for both polarizations simultaneously. Wideband dielectric mirrors including absorption losses were also studied yielding a bandwidth of about 50% with reflectivities larger than 99.5%. |
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Serial |
1577 |
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Author |
Svechnikov, S. I.; Antipov, S. V.; Vakhtomin, Y. B.; Goltsman, G. N.; Gershenzon, E. M.; Cherednichenko, S. I.; Kroug, M.; Kollberg, E. |
Title |
Conversion and noise bandwidths of terahertz NbN hot-electron bolometer mixers |
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Journal Article |
Year |
2001 |
Publication |
Physics of Vibrations |
Abbreviated Journal |
Physics of Vibrations |
Volume |
9 |
Issue |
3 |
Pages |
205-210 |
Keywords |
NbN HEB mixers |
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1069-1227 |
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no |
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Serial |
1551 |
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Author |
Cherednichenko, S.; Kroug, M.; Merkel, H.; Khosropanah, P.; Adam, A.; Kollberg, E.; Loudkov, D.; Gol'tsman, G.; Voronov, B.; Richter, H.; Huebers, H.-W. |
Title |
1.6 THz heterodyne receiver for the far infrared space telescope |
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Journal Article |
Year |
2002 |
Publication |
Phys. C: Supercond. |
Abbreviated Journal |
Phys. C: Supercond. |
Volume |
372-376 |
Issue |
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Pages |
427-431 |
Keywords |
NbN HEB mixers, applications |
Abstract |
A low noise heterodyne receiver is being developed for the terahertz range using a phonon-cooled hot-electron bolometric mixer based on 3.5 nm thick superconducting NbN film. In the 1–2 GHz intermediate frequency band the double-sideband receiver noise temperature was 450 K at 0.6 THz, 700 K at 1.6 THz and 1100 K at 2.5 THz. In the 3–8 GHz IF band the lowest receiver noise temperature was 700 K at 0.6 THz, 1500 K at 1.6 THz and 3000 K at 2.5 THz while it increased by a factor of 3 towards 8 GHz. |
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ISSN |
0921-4534 |
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no |
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1527 |
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Author |
Cherednichenko, S.; Rönnung, F.; Gol'tsman, G.; Kollberg, E.; Winkler, D. |
Title |
YBa2Cu3O7−δ hot-electron bolometer mixer |
Type |
Journal Article |
Year |
2000 |
Publication |
Phys. C: Supercond. |
Abbreviated Journal |
Phys. C: Supercond. |
Volume |
341-348 |
Issue |
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Pages |
2653-2654 |
Keywords |
YBCO HTS HEB mixers |
Abstract |
We present an investigation of hot-electron bolometric mixer based on YBa2Cu3O7−δ (YBCO) superconducting thin film. Mixer conversion loss, absorbed local oscillator power and intermediate frequency bandwidth was measured at the local oscillator frequency 600 GHz. The fabrication technique for nanoscale YBCO hot-electron bolometer (HEB) mixer integrated into planar antenna structure is described. |
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0921-4534 |
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no |
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1552 |
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Author |
Cherednichenko, S.; Drakinskiy, V. |
Title |
Low noise hot-electron bolometer mixers for terahertz frequencies |
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Journal Article |
Year |
2008 |
Publication |
J. Low Temp. Phys. |
Abbreviated Journal |
J. Low Temp. Phys. |
Volume |
151 |
Issue |
1-2 |
Pages |
575-579 |
Keywords |
HEB, mixer, gain bandwidth, MgB2 |
Abstract |
Hot-electron bolometer (HEB) mixers are used in many low noise heterodyne radio astronomical receivers. Their noise temperature is at the level of 10–15 times the quantum limit. However, their gain bandwidth is a serious limiting factor. Here we review the state of the art of the HEB mixers gain bandwidth for different materials and substrates. We compare the gain bandwidth of HEB mixers made on bulk substrates and thin membranes. Finally, results for MgB2 thin films for broadband HEB mixers are discussed. |
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0022-2291 |
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RPLAB @ lobanovyury @ |
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553 |
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