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Torgashin, M. Y., Koshelets, V. P., Dmitriev, P. N., Ermakov, A. B., Filippenko, L. V., & Yagoubov, P. A. (2007). Superconducting integrated receivers based on Nb-AlN-NbN circuits. IEEE Trans. Appl. Supercond., 17(2), 379–382.
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Jian Wei, David Olaya, Boris Karasik, Sergey Pereverzev, Andrei Sergeev, & Michael Gershenson. (2007). Ultra-sensitive hot-electron nanobolometers for terahertz astrophysics. ArXiv e-prints, 710.
Abstract: The background-limited spectral imaging of the early Universe requires spaceborne terahertz (THz) detectors with the sensitivity 2-3 orders of magnitude better than that of the state-of-the-art bolometers. To realize this sensitivity without sacrificing operating speed, novel detector designs should combine an ultrasmall heat capacity of a sensor with its unique thermal isolation. Quantum effects in thermal transport at nanoscale put strong limitations on the further improvement of traditional membrane-supported bolometers. Here we demonstrate an innovative approach by developing superconducting hot-electron nanobolometers in which the electrons are cooled only due to a weak electron-phonon interaction. At T<0.1K, the electron-phonon thermal conductance in these nanodevices becomes less than one percent of the quantum of thermal conductance. The hot-electron nanobolometers, sufficiently sensitive for registering single THz photons, are very promising for submillimeter astronomy and other applications based on quantum calorimetry and photon counting.
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Khosropanah, P., Gao, J. R., Laauwen, W. M., Hajenius, M., & Klapwijk, T. M. (2007). Low noise NbN hot electron bolometer mixer at 4.3 THz. Appl. Phys. Lett., 91, 221111 (1 to 3).
Abstract: We have studied the sensitivity of a superconducting NbN hot electron bolometer mixer integrated with a spiral antenna at 4.3 THz. Using hot/cold blackbody loads and a beam splitter all in vacuum, we measured a double sideband receiver noise temperature of 1300 K at the optimum local oscillator (LO) power of 330 nW, which is about 12 times the quantum noise (hnu/2kB). Our result indicates that there is no sign of degradation of the mixing process at the superterahertz frequencies. Moreover, a measurement method is introduced which allows us for an accurate determination of the sensitivity despite LO power fluctuations.
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Масленников, С. Н. (2007). Смесители на эффекте электронного разогрева для терагерцового и инфракрасного диапазонов. Ph.D. thesis, , .
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Koch, M. (2007). Terahertz communications: a 2020 vision. In NATO Security through Science Series (Vol. 2007, pp. 325–338).
Abstract: We discuss basic considerations for potential short-range THz communication systems which may replace or supplement present WLAN systems in 10–15 years from now. On the basis of a few fundamental estimations we show that such a system will need a line-of-sight connection between receiver and emitter. To circumvent the blocking of the direct line-of-sight connection indoor THz communication systems will also have to rely on non-line-of-sight paths which involve reflections off the walls. The reflectivity of the walls can be enhanced by dielectric mirrors. This new scheme makes steerable high-gain antennas a necessity. Hence, a wireless THz communication system can not be a simple extension of the existing technology of today's local area networks. Instead it involves completely new concepts and ideas that have not yet been worked upon.
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