Il'in, K. S., Karasik, B. S., Ptitsina, N. G., Sergeev, A. V., Gol'tsman, G. N., Gershenzon, E. M., et al. (1996). Electron-phonon-impurity interference in thin NbC films: electron inelastic scattering time and corrections to resistivity. In Czech. J. Phys. (Vol. 46, pp. 857–858).
Abstract: Complex study of transport properties of impure NbC films with the electron mean free pathl=0.6–13 nm show the crucial role of the electron-phonon-impurity interference (EPII). In the temperature range 20–70 K we found the interference correction to resistivity proportional to T2 and to the residual resistivity of the film. Using the comprehensive theory of EPII, we determine the electron coupling with transverse phonons and calculate the electron inelastic scattering time. Direct measurements of the inelastic electron scattering time using a response to a high-frequency amplitude modulated cw radiation agree well with the theory.
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Karasik, B. S., Zorin, M. A., Milostnaya, I. I., Elantev, A. I., Gol’tsman, G. N., & Gershenzon, E. M. (1995). Subnanosecond switching of YBaCuO films between superconducting and normal states induced by current pulse. J. Appl. Phys., 77(8), 4064–4070.
Abstract: A study is reported of the current switching in high‐quality YBaCuO films deposited onto NdGaO3 and ZrO2 substrates between superconducting (S) and normal (N) states. The films 60–120 nm thick prepared by laser ablation were structured into single strips between gold contacts. The time dependence of the resistance after application of the voltage step to the film was monitored. Experiment performed within certain ranges of voltage amplitudes and temperatures has shown the occurrence of the fast stage (shorter than 400 ps) both in S‐N and N‐S transitions. A fraction of the film resistance changing within this stage in the S‐N transition increases with the current amplitude. A subnanosecond N‐S stage becomes more pronounced for shorter pulses. The fast switching is followed by the much slower change of resistance. The mechanism of switching is discussed in terms of the hot‐electron phenomena in YBaCuO. The contributions of other thermal processes (e.g., a phonon escape from the film, a heat diffusion in the film and substrate, a resistive domain formation) in the subsequent stage of the resistance dynamic have been also discussed. The basic limiting characteristics (average dissipated power, energy needed for switching, maximum repetition rate) of a picosecond switch which is proposed to be developed are estimated.
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Gershenzon, E. M., Gol'tsman, G. N., Elantiev, A. I., Karasik, B. S., & Potoskuev, S. E. (1988). Intense electromagnetic radiation heating of electrons of a superconductor in the resistive state. Sov. J. Low Temp. Phys., 14(7), 414–420.
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Elant'ev, A. I., & Karasik, B. S. (1989). Effect of high-frequency current on Nb superconductive film in resistive state. Sov. J. Low Temp. Phys., 15(7), 379–383.
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Gershenzon, E. M., Gol'tsman, G. N., Elant'ev, A. I., Karasik, B. S., & Potoskuev, S. E. (1988). Intense electromagnetic radiation heating of superconductor electrons in resistive state. Fizika Nizkikh Temperatur, 14(7), 753–763.
Abstract: An experimental study is made of the effect of intense radiation in the millimeter and submillimeter ranges on thin and narrow Nb films in the resistive state. It is found that the excess resistance resulting from radiation and the dependence of its relaxation time on radiation intensity and transport current can be explained in terms of the effect of electron heating. Quantitative agreement is obtained between the experimental data and a homogeneous electron heating model.
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Karasik, B. S., & Elantiev, A. I. (1996). Noise temperature limit of a superconducting hot-electron bolometer mixer. Appl. Phys. Lett., 68(6), 853–855.
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Gershenzon, E. M., Gol'tsman, G. N., Karasik, B. S., Lugovaya, G. Y., Serebryakova, N. A., & Chinkova, E. V. (1992). Infrared radiation detectors on the base of electron heating in resistive state films from traditional superconducing materials. Sverkhprovodimost': Fizika, Khimiya, Tekhnika, 5(6), 1129–1140.
Abstract: Characteristics of infrared radiation detectors based on electron heating in thin superconducting films transformed at T ≤ Tc to a resistive state by transport current and, if necessary, by magnetic field are investigated. A comparison is made of the characteristics of the detectors fabricated of different materials: aluminium, niobium, Mo0.5Re0.5. Some devices with different topology of the reception area are considered. Electron heating detectors are comparable by their sensitivity with superconducting bolometers, but differ in a high fast-response.
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Gershenzon, E. M., Gershenzon, M. E., Gol'tsman, G. N., Karasik, B. S., Semenov, A. D., & Sergeev, A. V. (1987). Light-induced heating of electrons and the time of the inelastic electron-phonon scattering in the YBaCuO compound. JETP Lett., 46(6), 285–287.
Abstract: For the first time, measurements have been made on the electron energy relaxation time due to the electron--phonon interaction in films of the YBaCuO superconductor. The results indicate a significant intensification of the electron--phonon interaction in this compound as compared with normal superconducting metals.
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Gershenzon, E. M., Gol'tsman, G. N., Karasik, B. S., & Semenov, A. D. (1987). Measurement of the energy gap in the compound YBaCu3O9-δ on the basis of the IR absorption spectrum. JETP Lett., 46(5), 237–238.
Abstract: For the first time the long-wave infrared absorption spectrum has been measured by means of the bolometric effect and energy gap for high-temperature superconducting ceramics YBa/sub 2/Cu/sub 3/O/sub 9-delta/ has been determined from absorption threshold. 2delta/kT/sub c/ value is equal to 0.6.
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Gol'tsman, G. N., Goghidze, I. G., Kouminov, P. B., Karasik, B. S., Semenov, A. D., & Gershenzon, E. M. (1994). Influence of grain boundary weak links on the nonequilibrium response of YBaCuO thin films to short laser pulses. J. Supercond., 7(4), 751–755.
Abstract: The transient voltage response in both epitaxial and granular YBaCuO thin films to 80 ps pulses of YAG∶Nd laser radiation of wavelength 0.63 and 1.54 μm was studied. In the normal and resistive states both types of films demonstrate two components: a nonequilibrium picosecond component and a bolometric nanosecond one. The normalized amplitudes are almost the same for all films. In the superconducting state we observed a kinetic inductive response and two-component shape after integration. The normalized amplitude of the response in granular films is up to five orders of magnitude larger than in epitaxial films. We interpret the nonequilibrium response in terms of a suppression of the order parameter by the excess of quasiparticles followed by the change of resistance in the normal and resistive states or kinetic inductance in the superconducting state. The sharp rise of inductive response in granular films is explained both by a diminishing of the cross section for current percolation through the disordered network of Josephson weak links and by a decrease of condensate density in neighboring regions.
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