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Nebosis, R. S., Heusinger, M. A., Schatz, W., Renk, K. F., Gol’tsman, G. N., Karasik, B. S., et al. (1993). Ultrafast photoresponse of a structured YBa2Cu3O7-δ thin film to ultrashort FIR laser pulses. IEEE Trans. Appl. Supercond., 3(1), 2160–2162.
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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Банная, В. Ф., Веселова, Л. И., Гершензон, Е. М., Гусинский, Э. Н., & Литвак-Горская, Л. Б. (1990). Оценка точности метода определения раздельной концентрации примесей из измерений постоянной Холла. Физика и техника полупроводников, 24(12), 2145–2150.
Abstract: На примере p-Si⟨B,\,Ga⟩ с различной степенью компенсации проведена сравнительная оценка точности определения раздельной концентрации примесей по температурной зависимости концентрации дырок p(T) в случае одной и двух легирующих примесей с энергиями ионизации, различающимися менее чем в 2 раза. Исследована функция среднеквадратичного отклонения в пространстве параметров D(Nк, N2) (Nк, N1 и N2 — концентрации компенсирующих примесей бора и галлия соответственно, N2≫N1) в предположении, что N2, энергии B и Ga известны. Показано, что в случае двух легирующих примесей D(Nк, N1) в окрестностях минимума имеет «овражный» рельеф и при некоторых соотношениях между Nк и N1 разброс искомых величин превышает порядок, причем увеличение точности измерений p(T) существенного улучшения в вычислении параметров не дает. При одной легирующей примеси точность вычисления параметров высокая.
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Semenov, A. D., Goghidze, I. G., Gol’tsman, G. N., Sergeev, A. V., Aksaev, E. E., & Gershenzon, E. M. (1993). Non-equilibrium quasiparticle response to radiation and bolometric effect in YBaCuO films. IEEE Trans. Appl. Supercond., 3(1), 2132–2135.
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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Shah, J., Pinczuk, A., Gossard, A. C., & Wiegmann, W. (1985). Energy-loss rates for hot electrons and holes in GaAs quantum wells. Phys. Rev. Lett., 54, 2045–2048.
Abstract: We report the first direct determination of carrier-energy-loss rates in a semiconductor. These measurements provide fundamental insight into carrier-phonon interactions in semiconductors. Unexpectedly large differences are found in the energy-loss rates for electrons and holes in GaAs/AlGaAs quantum wells. This large difference results from an anomalously low electron-energy-loss rate, which we attribute to the presence of nonequilibrium optical phonons rather than the effects of reduced dimensionality or dynamic screening.
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Prokhodtsov, A., Golikov, A., An, P., Kovalyuk, V., Goltsman, G., Arakelyan, S., et al. (2019). Effect of silicon oxide coating on a silicon nitride focusing grating coupler efficiency. In EPJ Web Conf. (Vol. 220, 02009).
Abstract: The dependence of the efficiency of the focusing grating couplers on the period and filling factor before and after deposition of the upper silicon oxide layer was experimentally studied. The obtained data are of practical importance for tunable integrated-optical devices based on silicon nitride platform.
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