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Galin, M. A., Klushin, A. M., Kurin, V. V., Seliverstov, S. V., Finkel, M. I., Goltsman, G. N., et al. (2015). Towards local oscillators based on arrays of niobium Josephson junctions. Supercond. Sci. Technol., 28(5), 055002 (1 to 7).
Abstract: Various applications in the field of terahertz technology are in urgent need of compact, wide-tunable solid-state continuous wave radiation sources with a moderate power. However, satisfactory solutions for the THz frequency range are scarce yet. Here we report on coherent radiation from a large planar array of Josephson junctions (JJs) in the frequency range between 0.1 and 0.3 THz. The external resonator providing the synchronization of JJ array is identified as a straight fragment of a single-strip-line containing the junctions themselves. We demonstrate a prototype of the quasioptical heterodyne receiver with the JJ array as a local oscillator and a hot-electron bolometer mixer.
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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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Gershenzon, E. M., Gol'tsman, G. N., Gogidze, I. G., Gusev, Y. P., Elantiev, A. I., Karasik, B. S., et al. (1990). Millimeter and submillimeter wave range mixer based on electronic heating of superconducting films in the resistive state. Sov. Supercond., 3(10), 1582–1597.
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