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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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Ozhegov, R. V., Okunev, O. V., Gol’tsman, G. N., Filippenko, L. V., & Koshelets, V. P. (2009). Noise equivalent temperature difference of a superconducting integrated terahertz receiver. J. Commun. Technol. Electron., 54(6), 716–720.
Abstract: The dependence of the noise equivalent temperature difference (NETD) of a superconducting integrated receiver (SIR) on the receiver noise temperature and the inputsignal level has been investigated. An unprecedented NETD of 13±2 mK has been measured at a SIR noise temperature of 200 K, intermediate-frequency bandwidth of 4 GHz, and time constant of 1 s. With a decrease in the input signal, an improvement in the NETD is observed. This effect is explained by a reduction in the influence of the instabilities of the receiver power supply and the amplification circuit that occur when the input signal is decreased.
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Ожегов, Р. В., Окунев, О. В., Гольцман, Г. Н., Филиппенко, Л. В., & Кошелец, В. П. (2009). Флуктуационная чувствительность сверхпроводящего интегрального приемника терагерцового диапазона частот. Радиотех. электроник., 54(6), 750–755.
Abstract: Исследована зависимость флуктуационной чувствительности сверхпроводящего интегрального приемника (СИП) от шумовой температуры приемника и величины входного сигнала. Измерена рекордная флуктуационная чувствительность приемника (13 ± 2 мК), полученная при шумовой температуре приемника 200 К, ширине полосы промежуточных частот 4 ГГц и постоянной времени 1 с. При уменьшении входного сигнала наблюдалось улучшение флуктуационной чувствительности; предложено обÑŠяснение полученного эффекта: причиной является уменьшение влияния нестабильностей источников питания приемника и усилительного тракта при снижении входного сигнала.
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Smirnov, A. V., Baryshev, A. M., de Bernardis, P., Vdovin, V. F., Gol'tsman, G. N., Kardashev, N. S., et al. (2012). The current stage of development of the receiving complex of the millimetron space observatory. Radiophys. Quant. Electron., 54(8), 557–568.
Abstract: We present an overview of the state of the onboard receiving complex of the Millimetron space observatory in the development phase of its preliminary design. The basic parameters of the onboard equipment planned to create and required for astrophysical observations are considered. A review of coherent and incoherent detectors, which are central to each receiver of the observatory, is given. Their characteristics and limiting parameters feasible at the present level of technology are reported.
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Nikogosyan, A. S., Martirosyan, R. M., Hakhoumian, A. A., Makaryan, A. H., Tadevosyan, V. R., Goltsman, G. N., et al. (2019). Effect of absorption on the efficiency of terahertz radiation generation in the metal waveguide partially filled with nonlinear crystal LiNbO3, DAST or ZnTe. J. Contemp. Phys., 54(1), 97–104.
Abstract: The influence of terahertz (THz) radiation absorption on the efficiency of generation of coherent THz radiation in the system ‘nonlinear-optical crystal partially filling the cross section of a rectangular metal waveguide’ has been investigated. The efficiency of the nonlinear frequency conversion of optical laser radiation to the THz range depends on the loss in the system and the fulfillment of the phase-matching (FM) condition in a nonlinear crystal. The method of partially filling of a metal waveguide with a nonlinear optical crystal is used to ensure phase matching. The phase matching is achieved by numerical determination of the thickness of the nonlinear crystal, that is the degree of partial filling of the waveguide. The attenuation of THz radiation caused by losses both in the metal walls of the waveguide and in the crystal was studied, taking into account the dimension of the cross section of the waveguide, the degree of partial filling, and the dielectric constant of the crystal. It is shown that the partial filling of the waveguide with a nonlinear crystal results in an increase in the efficiency of generation of THz radiation by an order of magnitude, owing to the decrease in absorption.
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