Records |
Author |
Karasik, B.S.; Lindgren, M.; Zorin, M.A.; Danerud, M.; Winkler, D.; Trifonov, V.V.; Gol’tsman, G.N.; Gershenzon, E.M. |
Title |
Picosecond detection and broadband mixing of near-infrared radiation by YBaCuO films |
Type |
Conference Article |
Year |
1994 |
Publication |
Proc. SPIE |
Abbreviated Journal |
Proc. SPIE |
Volume |
2159 |
Issue |
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Pages |
68-76 |
Keywords |
YBCO HTS HEB mixer |
Abstract |
Nonequilibrium picosecond and bolometric responses of YBCO films 500 angstroms thick patterned into 20 X 20 micrometers 2 size structure to 17 ps laser pulses and modulated radiation of GaAs and CO2 lasers have been studied. The modulation frequencies up to 10 GHz for GaAs laser and up to 1 GHz for CO2 were attained. The use of small radiation power (1 – 10 mW/cm2 for cw radiation and 10 – 100 nJ/cm2 for pulse radiation) in combination with high sensitive read-out system made possible to avoid any non-linear transient processes caused by an overheating of sample above a critical temperature or S-N switching enhanced by an intense radiation. Responses due to the change of kinetic inductance were believed to be negligible. The only signals observed were caused by a small change of the film resistance either in the resistive state created by a bias current or in the normal state. The data obtained by means of pulse and modulation techniques are in agreement. The responsivity about 1 V/W was measured at 1 GHz modulation frequency both for 0.85 micrometers and 10.6 micrometers wavelengths. The sensitivity of high-Tc fast wideband infrared detector is discussed. |
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Spie |
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Nahum, M.; Villegier, J.-C. |
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High-Temperature Superconducting Detectors: Bolometric and Nonbolometric |
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1640 |
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Ekström, H.; Karasik, B.; Kollberg, E.; Yngvesson, K. S. |
Title |
Investigation of a superconducting hot electron mixer |
Type |
Conference Article |
Year |
1994 |
Publication |
Proc. 5th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 5th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
169-188 |
Keywords |
HEB mixers |
Abstract |
Mixing at 20 GHz in niobium superconducting thin film strips in the resistive state is studied. Experiments give evidence that electron-heating is the main cause of the non linear phenomena. The requirements on the mode of operation and on the film parameters for small conversion loss and the possibility of conversion gain are discussed. Measurements indicate a minimum intrinsic conversion loss around 1 dB with a sharp drop for the lowest voltage bias-points, and a DSB mixer noise temperature between 100 and 450 K at 20 GHz. The device output noise temperature at the mixer operating point can be as low as 30-50 K. A simple theory is presented, which is based on the assumption that the small signal resistance is linearly dependent on power. This type of mixer is considered very promising for use in low-noise heterodyne receivers at THz frequencies. |
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1642 |
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Gol'tsman, G.; Jacobsson, S.; Ekstrom, H.; Karasik, B.; Kollberg, E.; Gershenzon, E. |
Title |
Slot-line tapered antenna with NbN hot electron mixer for 300-360 GHz operation |
Type |
Conference Article |
Year |
1994 |
Publication |
Proc. 5th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 5th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
209-213a |
Keywords |
NbN HEB mixers |
Abstract |
NbN hot-electron mixers combined with slot-line tapered antennas on Si wdnitride membranes had been fabricated. Several strips of 1 gm wide and 5 tan long made from 100 A NbN film are inserted into the slot antenna. IV-curves under local oscillator power in 300-350 GHz frequency range and conversion gain dependencies on intermediate fre- quency in the 0.1-1 GHz range are measured and compared with that for 100 GHz frequency band. Our results show that pumped IV-curves and intermediate frequency bands are different for 100 GHz and 300 GHz frequency ranges. The interpretation exploits the fact that for the lowest radiation frequency the superconducting energy gap is larger than the radiation quantum energy while they are comparable at the higher frequency. Tha results show that such mixers have good perspectives for terahertz receiving technology. |
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1643 |
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0kunev, 0.; Dzardanov, A.; Ekstrom, H.; Jacobsson, S.; Kollberg, E.; Gol'tsman, G.; Gershenzon, E. |
Title |
NbN hot electron waveguide mixer for 100 GHz operation |
Type |
Conference Article |
Year |
1994 |
Publication |
Proc. 5th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 5th Int. Symp. Space Terahertz Technol. |
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Issue |
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Pages |
214-224 |
Keywords |
waveguide NbN HEB mixers |
Abstract |
NbN is a promising superconducting material used to develope hot- electron superconducting mixers with an IF bandwidth over 1 GHz. In the 100 GHz frequency range, the following parameters were obtained for NbN films 50 A thick: the noise temperature of the receiver (DSB) 1000 K; the conversion losses 10 d13, the IF bandwidth 1 GHz; the local oscillator power 1 /LW. An increase of NbN film thickness up to 80-100 A and increase of working temperature up to 7-8 K, and a better mixer matching may allow to broader the IF band up to 3 Gllz, to reduce the conversion losses down to 3-5 dB and the noise tempera- ture down to 200-300 K. |
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1644 |
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Author |
Elantev, Andrey I.; Karasik, Boris S. |
Title |
Noise temperature of a superconducting hot-electron mixer |
Type |
Conference Article |
Year |
1994 |
Publication |
Proc. 5th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 5th Int. Symp. Space Terahertz Technol. |
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Pages |
225 |
Keywords |
HEB mixers |
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1645 |
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Ekstrom, H.; Karasik, B.; Weikle, R.; Yngvesson, K. S.; Gol’tsman, G.; Kollberg, E.; Gershenzon, E. |
Title |
Mixers using superconducting Nb films in the resistive state |
Type |
Conference Article |
Year |
1993 |
Publication |
23rd European Microwave Conf. |
Abbreviated Journal |
23rd European Microwave Conf. |
Volume |
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Issue |
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Pages |
787-789 |
Keywords |
Nb HEB mixers |
Abstract |
The mixing of 20 GHz radiation in a Nb superconducting film in the resistive state was studied. The experiment gave evidence of electron-heating to be the origin of the non-linear phenomenon. The requirements on the operation mode and on the film parameters in order to obtain small conversion losses or even gain are determined. Our measurements indicate a conversion loss of about 6-8 dB. The hot-electron bolometer is considered to be very promising for use in heterodyne receivers in a wide frequency range from microwaves to terahertz frequencies. |
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1651 |
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Author |
Gershenzon, E. M.; Gol'tsman, G. N. |
Title |
Hot electron superconductive mixers |
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Conference Article |
Year |
1993 |
Publication |
Proc. 4th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 4th Int. Symp. Space Terahertz Technol. |
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Pages |
618-622 |
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HEB mixers |
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1656 |
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Kollberg, Erik L.; Gershenzon, E.; Goltsman, G.; Yngvesson, K. S. |
Title |
Hot electron mixers, the potential competition |
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Conference Article |
Year |
1992 |
Publication |
Proc. ESA Symp. on Photon Detectors for Space Instrumentation |
Abbreviated Journal |
Proc. ESA Symp. on Photon Detectors for Space Instrumentation |
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201-206 |
Keywords |
HEB mixers |
Abstract |
There is an urgent need in radio astronomy for low noise heterodyne receivers for frequencies above about 500 GHz. It is not certain that mixers based on superconducting quasiparticle tunnelling (SIS mixers) may turn out to be the answer to this need. In order to try to find an alternative way for realizing low noise heterodyne receivers for submillimeter waves, so called hot electron bolometric effects for mixing are now being investigated. Two basically different approaches are tried, one based on semiconductors and one on superconductors. Both methods are briefly discussed in this overview paper. |
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ESA Symposium on Photon Detectors for Space Instrumentation |
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1667 |
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Hübers, H.-W.; Semenov, A.; Richter, H.; Birk, Manfred; Krocka, Michael; Mair, Ulrich; Smirnov, K.; Gol'tsman, G.; Voronov, B. |
Title |
Terahertz heterodyne receiver with a hot-electron bolometer mixer |
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Conference Article |
Year |
2002 |
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Proc. Far-IR, Sub-mm, and mm Detector Technology Workshop |
Abbreviated Journal |
Proc. Far-IR, Sub-mm, and mm Detector Technology Workshop |
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NbN HEB mixers |
Abstract |
During the past decade major advances have been made regarding low noise mixers for terahertz (THz) heterodyne receivers. State of the art hot-electron-bolometer (HEB) mixers have noise temperatures close to the quantum limit and require less than a µW power from the local oscillator (LO). The technology is now at a point where the performance of a practical receiver employing such mixer, rather than the figures of merit of the mixer itself, are of major concern. We have incorporated a phonon-cooled NbN HEB mixer in a 2.5 THz heterodyne receiver and investigated the performance of the receiver. This yields important information for the development of heterodyne receivers such as GREAT (German receiver for astronomy at THz frequencies aboard SOFIA)[1] and TELIS (Terahertz limb sounder), a balloon borne heterodyne receiver for atmospheric research [2]. Both are currently under development at DLR. |
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Monterey, CA, USA |
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Wold, J.; Davidson, J. |
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4 pages; Unconfirmed but cited in https://kups.ub.uni-koeln.de/1622/1/bedorf.pdf; There is a Program of the Workshop: https://www.yumpu.com/en/document/view/7411055/far-ir-submm-mm-detector-technology-workshop-sofia-usra (there is no title of this article in the Program); There is also identical publication in Proc. ISSTT (Serial: 332, “A broadband terahertz heterodyne receiver with an NbN HEB mixer”). |
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1829 |
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Lindgren, M.; Zorin, M. A.; Trifonov, V.; Danerud, M.; Winkler, D.; Karasik, B. S.; Gol'tsman, G. N.; Gershenzon, E. M. |
Title |
Optical mixing in a patterned YBa2Cu3O7-δ thin film |
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Journal Article |
Year |
1994 |
Publication |
Appl. Phys. Lett. |
Abbreviated Journal |
Appl. Phys. Lett. |
Volume |
65 |
Issue |
26 |
Pages |
3398-3400 |
Keywords |
YBCO HTS HEB mixer, bandwidth |
Abstract |
Mixing of 1.56 µm infrared radiation from two lasers in a high quality YBa2Cu3O7-δ thin film, patterned to parallel strips, was demonstrated. A mixer bandwidth of 18 GHz, limited by the measurement system, was obtained. A model based on nonequilibrium electron heating gives a good fit to the data and predicts an intrinsic mixer bandwidth in excess of 100 GHz, operating in the whole infrared spectrum. Reduction of bolometric effects and ways to decrease the conversion loss of the mixer is discussed. The minimum conversion loss is expected to be ~10 dB. |
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0003-6951 |
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251 |
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Karasik, B. S.; Elantiev, A. I. |
Title |
Noise temperature limit of a superconducting hot-electron bolometer mixer |
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Journal Article |
Year |
1996 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl. Phys. Lett. |
Volume |
68 |
Issue |
6 |
Pages |
853-855 |
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HEB mixer noise temperature, Johnson noise, thermal fluctuation noise, noise bandwidth |
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0003-6951 |
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260 |
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Karasik, B. S.; Il'in, K. S.; Pechen, E. V.; Krasnosvobodtsev, S. I. |
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Diffusion cooling mechanism in a hot-electron NbC microbolometer mixer |
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Journal Article |
Year |
1996 |
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Applied Physics Letters |
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Appl. Phys. Lett. |
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68 |
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16 |
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2285-2287 |
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HEB mixer, diffusion cooling channel, diffusion channel |
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0003-6951 |
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262 |
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Hübers, H.-W.; Semenov, A.; Holldack, K.; Schade, U.; Wüstefeld, G.; Gol’tsman, G. |
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Time domain analysis of coherent terahertz synchrotron radiation |
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Journal Article |
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2005 |
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Appl. Phys. Lett. |
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Appl. Phys. Lett. |
Volume |
87 |
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18 |
Pages |
184103 (1 to 3) |
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NbN HEB mixers, applications |
Abstract |
The time structure of coherent terahertz synchrotron radiation at the electron storage ring of the Berliner Elektronensynchrotron und Speicherring Gesellschaft has been analyzed with a fast superconducting hot-electron bolometer. The emission from a single bunch of electrons was found to last ∼1500ps at frequencies around 0.4THz, which is much longer than the length of an electron bunch in the time domain (∼5ps). It is suggested that this is caused by multiple reflections at the walls of the beam line. The quadratic increase of the power with the number of electrons in the bunch as predicted for coherent synchrotron radiation and the transition from stable to bursting radiation were determined from a single storage ring fill pattern of bunches with different populations. |
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1457 |
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Kawamura, J.; Blundell, R.; Tong, C.-yu E.; Gol’tsman, G.; Gershenzon, E.; Voronov, B.; Cherednichenko, S. |
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Low noise NbN lattice-cooled superconducting hot-electron bolometric mixers at submillimeter wavelengths |
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Journal Article |
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1997 |
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Appl. Phys. Lett. |
Abbreviated Journal |
Appl. Phys. Lett. |
Volume |
70 |
Issue |
12 |
Pages |
1619-1621 |
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NbN HEB mixers |
Abstract |
Lattice-cooled superconducting hot-electron bolometric mixers are used in a submillimeter-wave waveguide heterodyne receiver. The mixer elements are niobium nitride film with 3.5 nm thickness and ∼10 μm2 area. The local oscillator power for optimal performance is estimated to be 0.5 μW, and the instantaneous bandwidth is 2.2 GHz. At an intermediate frequency centered at 1.4 GHz with 200 MHz bandwidth, the double sideband receiver noise temperature is 410 K at 430 GHz. The receiver has been used to detect molecular line emission in a laboratory gas cell. |
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1599 |
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Semenov, A. D.; Gousev, Y. P.; Nebosis, R. S.; Renk, K. F.; Yagoubov, P.; Voronov, B. M.; Gol’tsman, G. N.; Syomash, V. D.; Gershenzon, E. M. |
Title |
Heterodyne detection of THz radiation with a superconducting hot‐electron bolometer mixer |
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Journal Article |
Year |
1996 |
Publication |
Appl. Phys. Lett. |
Abbreviated Journal |
Appl. Phys. Lett. |
Volume |
69 |
Issue |
2 |
Pages |
260-262 |
Keywords |
NbN HEB mixers |
Abstract |
We report on the use of a superconducting hot‐electron bolometer mixer for heterodyne detection of terahertz radiation. Radiation with a wavelength of 119 μm was coupled to the mixer, a NbN microbridge, by a hybrid quasioptical antenna consisting of an extended hyperhemispherical lens and a planar logarithmic spiral antenna. We found, at an intermediate frequency of 1.5 GHz, a system double side band noise temperature of ≊40 000 K and conversion losses of 25 dB. We also discuss the possibilities of further improvement of the mixer performance. |
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1610 |
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