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Yagoubov, P., Gol'tsman, G., Voronov, B., Svechnikov, S., Cherednichenko, S., Gershenzon, E., et al. (1996). Quasioptical phonon-cooled NbN hot-electron bolometer mixer at THz frequencies. In Proc. 7th Int. Symp. Space Terahertz Technol. (pp. 303–317).
Abstract: In our experiments we tested phonon-cooled hot-electron bolometer (HEB) quasioptical mixer based on spiral antenna designed for 0.5-1.2 THz frequency band and fabricated on sapphire, Si-coated sapphire and high resistivity silicon substrates. HEB devices were produced from thin superconducting NbN film 3.5-6 nm thick with the critical temperature of about 11-12 K. For these devices we achieved the receiver noise temperature T R (DSB) = 3000 K in the 500-700 GHz frequency range and an IF bandwidth of 3-4 GHz. Prelimanary measurements at frequencies 1-1.2 THz resulted the receiver noise temperature about 9000 K (DSB).
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Semenov, A. D., Sergeev, A. V., Kouminov, P., Goghidze, I. G., Heusinger, M. A., Nebosis, R. S., et al. (1993). Transparency of YBCO film/substrate interfaces for thermal phonons determined by photoresponse measurements. In H. C. Freyhardt (Ed.), Proc. 1st European Conf. on Appl. Supercond. (Vol. 2, pp. 1443–1446).
Abstract: Direct measurements of the thermal boundary resistance were performed by means of the stationary method. In this approach the temperature of an electrically heated film is controlled by its dc resistance while an additional film on the same substrate is used as a thermometer monitoring substrate temperature. The temperature field in the substrate is then calculated to deduce the Kapitza temperature step at the interface between the heated strip and the substrate. The main statement of all afore-said papers is that experimental values of the thermal boundary resistance are too large to be explained by the acoustic mismatch model. In this paper we investigate transparency of YBaCuO film/substrate interfaces for thermal phonons by means of photoresponse measurements. We show that our data are in reasonable agreement with the acoustic mismatch theory.
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Voronov, B. M., Gershenzon, E. M., Gol'tsman, G. N., Gogidze, I. G., Gusev, Y. P., Zorin, M. A., et al. (1992). Picosecond range detector base on superconducting niobium nitride film sensitive to radiation in spectral range from millimeter waves up to visible light. Sverkhprovodimost': Fizika, Khimiya, Tekhnika, 5(5), 955–960.
Abstract: Fast-operating picosecond detector of electromagnetical radiation is developed on the basis of fine superconducting film of niobium nitride with high sensitivity within spectral range from millimetric waves up to visible light. Detector sensitive element represents structure covering narrow parallel strips with micron sizes included in the rupture of microstrip line. Detecting ability of the detector and time constant measured using amplitude-simulated radiation of reverse wave tubes and pulse radiation of picosecond gas and solid-body lasers, constitute D*≅1010 W-1·cm·Hz-1/2 and τ≤5 ps respectively, at 10 K temperature. The expected value of time constant of the detector at 10 K obtained via extrapolation of directly measured dependence that is, τ ∝ τ-1, constitutes 20 ps. Experimental data demonstrate that detection mechanism is linked with electron heating effect.
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Gershenzon, E. M., Gol'tsman, G. N., Dzardanov, A. L., Elant'ev, A. I., Zorin, M. A., Markin, A. G., et al. (1992). S-N switching of niobium and YBCO films: limit time and perspective of fast key element creation. Sverkhprovodimost': Fizika, Khimiya, Tekhnika, 5(12), 2386–2402.
Abstract: A study was made on processes of switching of thin niobium film strips between superconducting and normal states under the effect of optical radiation pulse and voltage step. The results are described satisfactorily by the model of spatial homogeneous electron heating. It is shown that limiting switching times can be equal to several shares of nanosecond at 4.2 K. Preliminary results for YBa2Cu3O-7-x films are presented. Prospects and advantages of creation of ducting structures of narrow streps, are discussed.
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Aksaev, E. E., Gershenzon, E. M., Gol'tsman, G. N., Mirskij, G. I., & Semenov, A. D. (1991). Submillimetric spectrometer-relaxometer based on backward-wave tubes with picosecond time resolution. Pribory i Tekhnika Eksperimenta, 34(2), 125–131.
Abstract: The high-sensitive automatic spectrometer-relaxometer based on backward-wave tubes in the range of 4÷0.25 mm was described permitting to study the response kinetics of sample under investigation in any point of this range with the resolution time of 10-11 s. The relaxation measurements were conducted using oscillation beats of two adequate tubes, the frequency of one of them was fixed, while that of the other one was changeable. The amplitude-frequency characteristic of the response under the conditions of synchronous reception was recorded at beat frequency variation from 107 to 1010 Hz. The high sensitivity was reached by decreasing the device recording band down to 100 Hz in the whole measuring range.
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Gershenzon, E. M., Gogidze, I. G., Goltsman, G. N., Semenov, A. D., & Sergeev, A. V. (1991). Picosecond response on optical-range emission in thin YBaCuO films. Pisma v Zhurnal Tekhnicheskoi Fiziki, 17(22), 6–10.
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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Aksaev, E. E., Gershenzon, E. M., Gol'tsman, G. N., Semenov, A. D., & Sergeev, A. V. (1989). Interaction of electrons with thermal phonons in YBa2Cu3O7-δ films at low temperatures. JETP Lett., 50(5), 283–286.
Abstract: The time of electron-phonon interaction tau(eph) in YBaCuO films at low temperatures is studied. This is measured as the time of resistance relaxation in the resistive state of the superconducter, and is also determined from the increase in resistance under the action of radiation. Consistent results of these methods show that resistance relaxation in the resistive state is caused by cooling of the electron subsystem with respect to the phonon subsystem. The time tau(eph) is found to be inversely proportional to the temperature and comes to 80 ps when T = 1.6 K and 5 ps when T = 30 K. 6 refs.
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Aksaev, E. E., Gershenzon, E. M., Gershenson, M. E., Goltsman, G. N., Semenov, A. D., & Sergeev, A. V. (1989). Prospects for using high-temperature superconductors to create electron bolometers. Pisma v Zhurnal Tekhnicheskoi Fiziki, 15(14), 88–93.
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Gershenzon, E. M., Gershenson, M. E., Goltsman, G. N., Karasik, B. S., Lyulkin, A. M., & Semenov, A. D. (1989). Fast-response superconducting electron bolometer. Pisma v Zhurnal Tekhnicheskoi Fiziki, 15(3), 88–92.
Abstract: The general design, operation, and performance characteristics of fast-response electronic bolometers using a thin superconducting Nb film on a leucosapphire substrate are briefly reviewed. The volt-watt sensitivity of the bolometrs is 2,000-200,000 V/W, the operating temperature is 1.6 K, and the time constant is 4-4.5 ns.
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Gershenzon, E. M., Gershenson, M. E., Goltsman, G. N., Lyulkin, A. M., Semenov, A. D., & Sergeev, A. V. (1989). Limiting characteristics of fast-response superconducting bolometers. Zhurnal Tekhnicheskoi Fiziki, 59(2), 11–120.
Abstract: Теоретически и экспериментально исследовано физическое ограничение быстродействия сверхпроводящего болометра. Показано, что минимальная постоянная времени реализуется в условиях электронного разогрева и определяется процессом неупругого электрон-фонон-ного взаимодействия. Сформулированы требования к конструкции «электронного болометра» для достижения предельной чувствительности. Проведено сравнение характеристик электронного болометра и обычных болометров различных типов.
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