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Author Nebosis, R. S.; Heusinger, M. A.; Schatz, W.; Renk, K. F.; Gol’tsman, G. N.; Karasik, B. S.; Semenov, A. D.; Gershenzon, E. M.
Title Ultrafast photoresponse of a structured YBa2Cu3O7-δ thin film to ultrashort FIR laser pulses Type Journal Article
Year 1993 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 3 Issue 1 Pages 2160-2162
Keywords YBCO HTS detectors
Abstract The authors have investigated the photoinduced voltage response of a current-carrying structured YBa2Cu3O7-δ thin film to ultrashort far-infrared (FIR) laser pulses in the frequency range from 0.7 THz to 7 THz. The detector has shown an almost constant sensitivity of 1 mV/W and a noise equivalent power of less than 5*10/sup -7/ W/ square root Hz. The temperature dependence of the decay time of the detector signal was studied for temperatures around the transition temperature of the film ( approximately 80 K). For a detector temperature where dR/dT had its maximum, the authors observed bolometric signals with decay times of about 2 ns, and for lower temperatures they observed nonbolometric signals with decay times of approximately 120 ps; the duration of the nonbolometric signals was limited by the time resolution of the electronic registration equipment.
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Call Number Serial 1658
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Author Semenov, A. D.; Goghidze, I. G.; Gol’tsman, G. N.; Sergeev, A. V.; Aksaev, E. E.; Gershenzon, E. M.
Title Non-equilibrium quasiparticle response to radiation and bolometric effect in YBaCuO films Type Journal Article
Year 1993 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 3 Issue 1 Pages 2132-2135
Keywords YBCO HTS HEB detectors
Abstract The voltage photoresponse of structured current biased YBCO films on different substrates to 20-ps laser pulses of 0.63- mu m and 1.54- mu m wavelengths and to continuously modulated radiation of 2-mm wavelength is measured to temperatures around Tc. Fast picosecond decay of the response to pulsed radiation is followed by slow exponential relaxation with a nanosecond characteristic time depending on the substrate material and film dimensions. The slow component does not depend on wavelength and is attributed to the bolometric effect, while the magnitude of the fast component associated with nonequilibrium response rises with wavelength. More than an order-of-magnitude increase of the nonequilibrium response is seen from near-infrared to millimeter-wave range. This dependence plausibly reflects the low efficiency of multiplication of photoexcited electrons in YBaCuO compared to conventional superconductors.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1558-2515 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1659
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Author Gerecht, E.; Musante, C. F.; Zhuang, Y.; Yngvesson, K. S.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
Title NbN hot electron bolometric mixerss—a new technology for low-noise THz receivers Type Journal Article
Year 1999 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 47 Issue 12 Pages 2519-2527
Keywords NbN HEB mixers
Abstract New advances in hot electron bolometer (HEB) mixers have recently resulted in record-low receiver noise temperatures at terahertz frequencies. We have developed quasi-optically coupled NbN HEB mixers and measured noise temperatures up to 2.24 THz, as described in this paper. We project the anticipated future performance of such receivers to have even lower noise temperature and local-oscillator power requirement as well as wider gain and noise bandwidths. We introduce a proposal for integrated focal plane arrays of HEB mixers that will further increase the detection speed of terahertz systems.
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ISSN 1557-9670 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1560
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Author Gershenzon, E. M.; Gol’tsman, G. N.; Dzardanov, A. L.; Zorin, M. A.
Title Ultrafast superconductive switch Type Journal Article
Year 1991 Publication IEEE Trans. Magn. Abbreviated Journal IEEE Trans. Magn.
Volume 27 Issue 2 Pages 2844-2846
Keywords Nb superconducting switch
Abstract The transition from superconductive to resistive state caused by infrared radiation and bias current pulses was investigated in order to minimize switching time tau and driving power W. Experimental results for Nb microstrips confirm the correctness of calculations based on the model of electron heating. For Nb switches, tau measured directly is 0.3-0.8 ns for radiation pulses and 1-3 ns for bias current pulses at T=4.2 K, while for YBaCuO switches at T=77 K it is expected to be several picoseconds. For an YBaCuO sample with the dimensions of 5*2*0.15 mu m/sup 2/, W was 10 mW, and it can be further reduced to the order of several microwatts by decreasing the volume of the sample.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1941-0069 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1680
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Author Gershenzon, E. M.; Gol’tsman, G. N.; Semenov, A. D.; Sergeev, A. V.
Title Mechanism of picosecond response of granular YBaCuO films to electromagnetic radiation Type Journal Article
Year 1991 Publication IEEE Trans. Magn. Abbreviated Journal IEEE Trans. Magn.
Volume 27 Issue 2 Pages 1321-1324
Keywords YBCO HTS detectors
Abstract Ultrafast mechanisms of radiation detection in granular YBaCuO films are studied in the wide wavelength range from millimeter waves to near infrared. With an increase in radiation frequency, the Josephson detection at the grain-boundary weak links is replaced by electron heating into the grains. This change occurs in the submillimeter wavelength range. The electron-phonon relaxation time tau /sub eph/ is determined from direct measurements, quasi-stationary electron heating measurements, and the frequency dependence of the current at which maximum voltage shift is observed. The temperature dependence of tau /sub eph/ at T<or=40 K was found to be tau /sub eph/ approximately T/sup -1/. The results show that detectors with a response time of a few picoseconds at nitrogen temperature are attainable.
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ISSN 1941-0069 ISBN Medium
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Notes Approved no
Call Number Serial 1679
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Author Gershenzon, E. M.; Gol’tsman, G. N.; Gousev, Y. P.; Elant’ev, A. I.; Semenov, A. D.
Title Electromagnetic radiation mixer based on electron heating in resistive state of superconductive Nb and YBaCuO films Type Journal Article
Year 1991 Publication IEEE Trans. Magn. Abbreviated Journal IEEE Trans. Magn.
Volume 27 Issue 2 Pages 1317-1320
Keywords YBCO, HTS, Nb HEB mixers
Abstract A theory of an electron-heating mixer which makes it possible to calculate all the characteristics of the device is developed. It is shown that positive conversion gain is possible for such a mixer in the millimeter to near-infrared wavelength range. The dynamic range and the optimum heterodyne power can be selected from a very wide interval by varying the mixing element volume. Measurements made for Nb within the frequency range of 120-750 GHz confirm the theory. The conversion loss obtained at T=1.6 K and normalized to the element reaches 0.3 dB in the intermediate frequency band of 40 MHz; the possible noise temperature is 50 K. The estimation of noise temperature and output band for YBaCuO at T=77 yields 200 K and more than 10 GHz, respectively.
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ISSN 1941-0069 ISBN Medium
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Notes Approved no
Call Number Serial 1681
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Author Gerecht, E.; Musante, C. F.; Yngvesson, K. S.; Waldman, J.; Gol'tsman, G. N.; Yagoubov, P. A.; Voronov, B. M.; Gershenzon, E. M.
Title Optical coupling and conversion gain for NbN HEB mixer at THz frequencies Type Conference Article
Year 1997 Publication Proc. 4-th Int. Semicond. Device Research Symp. Abbreviated Journal Proc. 4-th Int. Semicond. Device Research Symp.
Volume Issue Pages 47-50
Keywords NbN HEB mixers
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Address Charlottesville, Virginia
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Call Number Serial 1601
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Author Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Yngvesson, K. S.
Title Hot electron bolometer detectors and mixers based on a superconducting-two-dimensional electron gas-superconductor structure Type Conference Article
Year 1997 Publication Proc. 4-th Int. Semicond. Device Research Symp. Abbreviated Journal Proc. 4-th Int. Semicond. Device Research Symp.
Volume Issue Pages 163-166
Keywords S-2DEG-S HEB mixers, detectors, AlGaAs/GaAs heterostructures, NbN
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Call Number Serial 1603
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Author Yagoubov, P.; Kroug, M.; Merkel, H.; Kollberg, E.; Gol'tsman, G.; Svechnikov, S.; Gershenzon, E.
Title Noise temperature and local oscillator power requirement of NbN phonon-cooled hot electron bolometric mixers at terahertz frequencies Type Journal Article
Year 1998 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 73 Issue 19 Pages 2814-2816
Keywords NbN HEB mixers, noise temperature, local oscillator power
Abstract In this letter, the noise performance of NbN-based phonon-cooled hot electron bolometric quasioptical mixers is investigated in the 0.55–1.1 THz frequency range. The best results of the double-sideband <cd><2018>DSB<cd><2019> noise temperature are: 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz, and 1250 K at 1.1 THz. The water vapor in the signal path causes significant contribution to the measured receiver noise temperature around 1.1 THz. The devices are made from 3-nm-thick NbN film on high-resistivity Si and integrated with a planar spiral antenna on the same substrate. The in-plane dimensions of the bolometer strip are typically 0.2Ï«2 um. The amount of local oscillator power absorbed in the bolometer is less than 100 nW.
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Notes Approved no
Call Number Serial 911
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Author Ekstörm, H.; Kollberg, E.; Yagoubov, P.; Gol'tsman, G.; Gershenzon, E.; Yngvesson, S.
Title Gain and noise bandwidth of NbN hot-electron bolometric mixers Type Journal Article
Year 1997 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 70 Issue 24 Pages 3296-3298
Keywords NbN HEB mixers, conversion loss, conversion gain, U-factor technique
Abstract We have measured the noise performance and gain bandwidth of 35 Å thin NbN hot-electron mixers integrated with spiral antennas on silicon substrate lenses at 620 GHz. The best double-sideband receiver noise temperature is less than 1300 K with a 3 dB bandwidth of ≈5 GHz. The gain bandwidth is 3.2 GHz. The mixer output noise dominated by thermal fluctuations is 50 K, and the intrinsic conversion gain is about −12 dB. Without mismatch losses and excluding the loss from the beamsplitter, we expect to achieve a receiver noise temperature of less than 700 K.
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Call Number Serial 279
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Author 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 Type 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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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 251
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Author Verevkin, A. A.; Ptitsina, N. G.; Chulcova, G. M.; Gol'Tsman, G. N.; Gershenzon, E. M.; Yngvesson, K. S.
Title Determination of the limiting mobility of a two-dimensional electron gas in AlxGa1-xAs/GaAs heterostructures and direct measurement of the energy relaxation time Type Journal Article
Year 1996 Publication Phys. Rev. B Condens. Matter. Abbreviated Journal Phys. Rev. B Condens. Matter.
Volume 53 Issue 12 Pages R7592-R7595
Keywords 2DEG, AlGaAs/GaAs heterostructures
Abstract We present results for a method to measure directly the energy relaxation time (τe) for electrons in a single AlxGa1−xAs/GaAs heterojunction; measurements were performed from 1.6 to 15 K under quasiequilibrium conditions. We find τeαT−1 below 4 K, and τe independent of T above 4 K. We have also measured the energy-loss rate, ⟨Q⟩, by the Shubnikov-de Haas technique, and find ⟨Q⟩α(T3e−T3) for T<~4.2 K; Te is the electron temperature. The values and temperature dependence of τe and ⟨Q⟩ for T<4 K agree with calculations based on piezoelectric and deformation potential acoustic phonon scattering. At 4.2 K, we can also estimate the momentum relaxation time, τm, from our measured τe. This leads to a preliminary estimate of the phonon-limited mobility at 4.2 K of μ=3×107 cm2/Vs (ns=4.2×1011 cm−2), which agrees well with published numerical calculations, as well as with an earlier indirect estimate based on measurements on a sample with much higher mobility.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829 ISBN Medium
Area Expedition Conference
Notes PMID:9982274 Approved no
Call Number Serial 1612
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Author Nebosis, R. S.; Heusinger, M. A.; Semenov, A. D.; Lang, P. T.; Schatz, W.; Steinke, R.; Renk, K. F.; Gol'tsman, G. N.; Karasik, B. S.; Gershenzon, E. M.
Title Ultrafast photoresponse of an YBa2Cu3O7-δ film to far-infrared radiation pulses Type Journal Article
Year 1993 Publication Opt. Lett. Abbreviated Journal Opt. Lett.
Volume 18 Issue 2 Pages 96-97
Keywords YBCO HTS detectors
Abstract We report the observation of an ultrafast photoresponse of a high-T(c), film to far-infrared radiation pulses. The response of a sample, consisting of a current-carrying structured YBa(2)Cu(3)O(7-delta) film cooled to liquid-nitrogen temperature, was studied by use of ultrashort laser pulses from an optically pumped far-infrared laser in the frequency range from 0.7 to 7 THz. We found that the response time was limited by the time resolution, 120 ps, of our electronic registration equipment.
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Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-9592 ISBN Medium
Area Expedition Conference
Notes PMID:19802049 Approved no
Call Number Serial 1660
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Author Sergeev, A. V.; Semenov, A. D.; Kouminov, P.; Trifonov, V.; Goghidze, I. G.; Karasik, B. S.; Gol’tsman, G. N.; Gershenzon, E. M.
Title Transparency of a YBa2Cu3O7-film/substrate interface for thermal phonons measured by means of voltage response to radiation Type Journal Article
Year 1994 Publication Phys. Rev. B Condens. Matter. Abbreviated Journal Phys. Rev. B Condens. Matter.
Volume 49 Issue 13 Pages 9091-9096
Keywords YBCO films
Abstract The transparency of a film/substrate interface for thermal phonons was investigated for YBa2Cu3O7 thin films deposited on MgO, Al2O3, LaAlO3, NdGaO3, and ZrO2 substrates. Both voltage response to pulsed-visible and to continuously modulated far-infrared radiation show two regimes of heat escape from the film to the substrate. That one dominated by the thermal boundary resistance at the film/substrate interface provides an initial exponential decay of the response. The other one prevailing at longer times or smaller modulation frequencies causes much slower decay and is governed by phonon diffusion in the substrate. The transparency of the boundary for phonons incident from the film on the substrate and also from the substrate on the film was determined separately from the characteristic time of the exponential decay and from the time at which one regime was changed to the other. Taking into account the specific heat of optical phonons and the temperature dependence of the group velocity of acoustic phonons, we show that the body of experimental data agrees with acoustic mismatch theory rather than with the model that assumes strong diffusive scattering of phonons at the interface.
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ISSN 0163-1829 ISBN Medium
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Notes PMID:10009690 Approved no
Call Number Serial 1648
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Author Gershenzon, E. M.; Gogidze, I. G.; Goltsman, G. N.; Semenov, A. D.; Sergeev, A. V.
Title Picosecond response on optical-range emission in thin YBaCuO films Type Journal Article
Year 1991 Publication Pisma v Zhurnal Tekhnicheskoi Fiziki Abbreviated Journal Pisma v Zhurnal Tekhnicheskoi Fiziki
Volume 17 Issue 22 Pages 6-10
Keywords YBCO HTS detectors
Abstract Целью настоящей работы является целенаправленный поиск пико-секундного отклика на оптическое излучение выяснение оптималь­ных условий его наблюдения, а также сравнение характеристик не­равновесных эффектов в оптическом и субмиллиметровом диапазонах.
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Publisher Place of Publication Editor
Language Russian Summary Language Original Title
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Area Expedition Conference
Notes Approved no
Call Number Serial 1684
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