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Zhang, W., Li, N., Jiang, L., Miao, W., Lin, Z. - H., Yao, Q. - J., et al. (2007). Noise behaviour of a THz superconducting hot-electron bolometer mixer. Chinese Phys. Lett., 24(6), 1778–1781.
Abstract: A quasi-optical superconducting NbN hot-electron bolometer (HEB) mixer is measured in the frequency range of 0.5–2.5 THz for understanding of the frequency dependence of noise temperature of THz coherent detectors. It has been found that noise temperature increasing with frequency is mainly due to the coupling loss between the quasi-optical planar antenna and the superconducting HEB bridge when taking account of non-uniform distribution of high-frequency current. With the coupling loss corrected, the superconducting HEB mixer demonstrates a noise temperature nearly independent of frequency.
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Chen, J., Kang, L., Jin, B. B., Xu, W. W., Wu, P. H., Zhang, W., et al. (2008). Properties of terahertz superconducting hot electron bolometer mixers. Int. J. Terahertz Sci. Technol., 1(1), 37–41.
Abstract: A quasi-optical superconducting niobium nitride (NbN) hot electron bolometer (HEB) mixer has been fabricated and measured in the terahertz (THz) frequency range of 0.5~2.52 THz. A receiver noise temperature of 2000 K at 2.52 THz has been obtained for the mixer without corrections. Also, the effect of a Parylene C anti-reflection (AR) coating on the silicon (Si) lens has been studied.
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Korneeva, Y. P., Trifonov, A. V., Vakhtomin, Y. B., & Smirnov, K. V. (2011). Design of resonator for superconducting single-photon detector. Rus. J. Radio Electron., (12).
Abstract: A resonator for superconducting single-photon detector is designed. Near 60% coupling with a radiation propagating from a dielectric substrate of optical fiber is demonstrated to be achieved for typical values of the detector’s film sheet resistance.
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Gershenzon, E. M., Gol'tsman, G. N., & Semenov, A. D. (1983). Submillimeter backward wave tube spectrometer for measuring superconducting film transmission. Pribory i Tekhnika Eksperimenta, 26(5), 134–137.
Abstract: A spectrometer employing six backward wave tubes is described. It is intended for investigation of superconductors in the 0.2-3 mm range of wave lengths. During the measurement of the transmission spectrum it is possible to determine the energy gap for superconduct1ng films 50 to 4000 A thick. The transmission factor can vary from 10-1 to 10-9. Spectrum of relation of film transmission factors in superconducting and normal states is measured for determining the energy gap 2 Δ. The transmission spectrum obtained by means of a computer for vanadium film 300 A thick is given as an example. The energy gap 2 Δ = 1.4 MeV
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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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