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Semenov, A. D., Hiibers, H. - W., Richter, H., Smirnov, K., Gol'tsman, G. N., Kaurova, N., et al. (2003). Superconducting hot-electron bolometer mixer for terahertz heterodyne receivers. In Proc. 14th Int. Symp. Space Terahertz Technol. (pp. 33–40).
Abstract: A number of on-going astronomical and atmospheric research programs are aimed to the Terahertz (THz) spectral region. At frequencies above about 1.4 THz heterodyne receivers planned for these missions will use superconducting hot-electron bolometers as a mixers. We present recent results of the terahertz antenna development of superconducting NbN hot-electron bolometer mixer for GREAT (German Receiver for Astronomy at Terahertz Frequencies, to be used aboard of SOFIA) and TELIS (Terahertz Limb Sounder). The mixer is incorporated into hybrid antenna consisting of a planar feed antenna, which has either logarithmic spiral or double-slot configuration, and hyper hemispherical silicon lens. The hybrid antenna showed almost frequency independent and symmetric radiation pattern with the beam-width slightly broader than expected for diffraction limited antenna. The noise temperature as well as its spectral dependence changes with the bolometer sizes that provides additional tool for mixer optimization. FTS spectra measured in the direct detection regime agreed with the noise temperature spectra.
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Tong, C. - Y. E., Kawamura, J., Todd, R. H., Papa, D. C., Blundell, R., Smith, M., et al. (2000). Successful operation of a 1 THz NbN hot-electron bolometer receiver. In Proc. 11th Int. Symp. Space Terahertz Technol. (pp. 49–59).
Abstract: A phonon-cooled NbN superconductive hot-electron bolometer receiver covering the frequency range 0.8-1.04 THz has successfully been used for astronomical observation at the Sub-Millimeter Telescope Observatory on Mount Graham, Arizona. This waveguide heterodyne receiver is a modified version of our fixed-tuned 800 GHz HEB receiver to allow for operation beyond 1 THz. The measured noise temperature of this receiver is about 1250 K at 0.81 THz, 560 K at 0.84 THz, and 1600 K at 1.035 THz. It has a 1 GHz wide IF bandwidth, centered at 1.8 GHz. This receiver has recently been used to detect the CO (9-8) molecular line emission at 1.037 THz in the Orion nebula. This is the first time a ground-based heterodyne receiver has been used to detect a celestial source above 1 THz.
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Dauler, E., Kerman, A., Robinson, B., Yang, J., Voronov, B., Goltsman, G., et al. (2009). Photon-number-resolution with sub-30-ps timing using multi-element superconducting nanowire single photon detectors. J. Modern Opt., 56(2), 364–373.
Abstract: A photon-number-resolving detector based on a four-element superconducting nanowire single photon detector is demonstrated to have sub-30-ps resolution in measuring the arrival time of individual photons. This detector can be used to characterize the photon statistics of non-pulsed light sources and to mitigate dead-time effects in high-speed photon counting applications. Furthermore, a 25% system detection efficiency at 1550 nm was demonstrated, making the detector useful for both low-flux source characterization and high-speed photon-counting and quantum communication applications. The design, fabrication and testing of this detector are described, and a comparison between the measured and theoretical performance is presented.
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Nagatsuma, T., Hirata, A., Royter, Y., Shinagawa, M., Furuta, T., Ishibashi, T., et al. (2000). A 120-GHz integrated photonic transmitter. In Proc. International topical meeting on microwave photonics (MWP 2000) (pp. 225–228).
Abstract: A photonics-based 120-GHz transmitter has been developed. A photodiode, a planar antenna and a silicon lens were integrated to form a compact millimeter-wave (MMW) emitter. The MMW signal emitted from the transmitter has been detected with a waveguide-mounted Schottky diode. The received power exceeded 100 μW, which is the highest value ever reported for photonic MMW transmitter at frequencies of >100 GHz
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Семенов, А. В., Девятов, И. А., Рябчун, С. А., Масленников, С. Н., Масленникова, А. С., Ларионов, П. А., et al. (2011). Поглощение терагерцового электромагнитного излучения в “грязной” сверхпроводниковой пленке при произвольном виде спектральных функций. Ж. Радиоэлектрон., 10, 7.
Abstract: A problem of absorption of high-frequency electromagnetic field in dirty superconductor is treated within Keldysh technic. Expression for the source term in the kinetic equation for quasiparticle distribution function is derived. The result is significant for deriving a consistent microscopic theory of superconducting detectors for terahertz frequency range, perspective detectors on kinetic inductance of current-biased superconducting strip and on Josephson inductance of tunnel.
В технике Келдыша рассмотрена задача о поглощении мощности высокочастотного электромагнитного поля в сверхпроводнике, удовлетворяющем условию грязного предела. Получено выражение для члена источника в кинетическом уравнении для функции распределения квазичастиц, справедливое при произвольном виде спектральных функций. Этот результат имеет значение для развития последовательной микроскопической теории сверхпроводниковых детекторов излучения терагерцового диапазона, в частности, перспективных детекторов на кинетической индуктивности смещённой током сверхпроводниковой полоски и джозефсоновской индуктивности туннельного контакта.
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