Semenov, A., Richter, H., Hübers, H. - W., Petrenko, D., Tretyakov, I., Ryabchun, S., et al. (2014). Optimization of the intermediate frequency bandwidth in the THz HEB mixers. In Proc. 25th Int. Symp. Space Terahertz Technol. (54).
Abstract: We report on the studies of the intermediate frequency (IF) bandwidth of quasi-optically coupled NbN hot-electron bolometer (HEB) mixers which are aimed at the optimization of the mixer performance at terahertz frequencies. Extension of the IF bandwidth due to the contribution of electron diffusion to the heat removal from NbN microbolometers has been already demonstrated for NbN HEBs at subterahertz frequencies. However, reducing the size of the microbolometer causes degradation of the noise temperature. Using in-situ multilayer manufacturing process we succeeded to improve the transparency of the contacts for electrons which go away from microbolometer to the metallic antenna. The improved transparency and hence coupling efficiency counterbalances the noise temperature degradation. HEB mixers were tested in a laboratory heterodyne receiver with a narrow-band cold filter which allowed us to eliminate direct detection. We used a local oscillator with a quantum cascade laser (QCL) at a frequency of 4.745 THz [1] which was developed for the H-Channel of the German Receiver for Astronomy at Terahertz frequencies (GREAT). Both the noise and gain bandwidth were measured in the IF range from 0.5 to 8 GHz using the hot-cold technique and preliminary calibrated IF analyzer with a tunable microwave filter. For optimized HEB geometry we found the noise bandwidth as large as 7 GHz. We compare our results with the conventional and the hot-spot mixer models and show that further extension of the IF bandwidth should be possible via improving the sharpness of the superconducting transition. The cross characterization of the HEB mixer was performed in the test bed of GREAT at the Max-Planck-Institut für Radioastronomie with the same QCL LO and delivered results which were consistent with the laboratory studies.
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Лесс, Ю. А., & Кирсанов, Ю. А. (2015). Былое и думы. Посвящение эпохе Н. Н. Малова, Е. М. Гершензона, В. С. Эткина.
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Флоря, И. Н. (2009). Ультрабыстрый однофотонный детектор для оптических применений. In Науч. сессия МИФИ (pp. 45–46).
Abstract: Представлен сверхпроводниковый однофотонный детектор (SSPD) на основе ультратонкой пленки NbN, обладающий рекордным быстродействием. Активный элемент выполнен в виде N сверхпроводящих полосок соединенных параллельно, покрывающих площадку размером 10 мкм х 10 мкм. Для SSPD с N=12 длительность импульса напряжения составляет 200 пс. Полученные результаты открывают путь к детекторам обладающими скоростью счета свыше 1 ГГц, что делает SSPDs весьма привлекательными во многих применениях, в частности для квантовой криптографии. SSPD хорошо согласуется с оптоволокном и легко может быть интегрирован в полностью готовую для работы приемную систему.
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Семенов, А. В. (2010). Проскальзывание фазы, поглощение электромагнитного излучения и формирование отклика в детекторах на основе узких полосок сверхпроводников. Ph.D. thesis, , .
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Tretyakov, I., Shurakov, A., Perepelitsa, A., Kaurova, N., Svyatodukh, S., Zilberley, T., et al. (2019). Silicon room temperature IR detectors coated with Ag2S quantum dots. In Proc. IWQO (pp. 369–371).
Abstract: For decades silicon has been the chief technological semiconducting material of modern microelectronics. Application of silicon detectors in optoelectronic devices are limited to the visible and near infrared ranges, due to their transparency for radiation with a wavelength higher than 1.1 μm. The expansion Si absorption towards longer wave lengths is a considerable interest to optoelectronic applications. In this work we present an elegant and effective solution to this problem using Ag2S quantum dots, creating impurity states in Si to cause sub-band gap photon absorption. The sensitivity of room temperature zero-bias Si_Ag2S detectors, which we obtained is 1011 cmHzW . Given the variety of QDs parameters such as: material, dimensions, our results open a path towards the future study and development of Si detectors for technological applications.
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