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Vakhtomin YB, Finkel MI, Antipov SV, Smirnov KV, Kaurova NS, Drakinskii VN, et al. The gain bandwidth of mixers based on the electron heating effect in an ultrathin NbN film on a Si substrate with a buffer MgO layer. J of communications technol & electronics. 2003;48(6):671–5.
Abstract: Measurements of the intermediate frequency band 900 GHz of mixers based on the electron heating effect (EHE) in 2-nm- and 3.5-nm-thick superconducting NbN films sputtered on MgO and Si substrates with buffer MgO layers are presented. A 2-nm-thick superconducting NbN film with a critical temperature of 9.2 K has been obtained for the first time using a buffer MgO layer.
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Meledin D, Tong CY-E, Blundell R, Kaurova N, Smirnov K, Voronov B, et al. Study of the IF bandwidth of NbN HEB mixers based on crystalline quartz substrate with an MgO buffer layer. IEEE Trans Appl Supercond. 2003;13(2):164–7.
Abstract: In this paper, we present the results of IF bandwidth measurements on 3-4 nm thick NbN hot electron bolometer waveguide mixers, which have been fabricated on a 200-nm thick MgO buffer layer deposited on a crystalline quartz substrate. The 3-dB IF bandwidth, measured at an LO frequency of 0.81 THz, is 3.7 GHz at the optimal bias point for low noise receiver operation. We have also made measurements of the IF dynamic impedance, which allow us to evaluate the intrinsic electron temperature relaxation time and self-heating parameters at different bias conditions.
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Tinkham M, Free JU, Lau CN, Markovic N. Hysteretic I–V curves of superconducting nanowires. Phys. Rev. B. 2003;68:134515(1 to 7).
Abstract: Experimental I–V curves of superconducting MoGe nanowires show hysteresis for the thicker wires and none for the thinner wires. A rather quantitative account of these data for representative wires is obtained by numerically solving the one-dimensional heat flow equation to find a self-consistent distribution of temperature and local resistivity along the wire, using the measured linear resistance R(T) as input. This suggests that the retrapping current in the hysteretic I–V curves is primarily determined by heating effects, and not by the dynamics of phase motion in a tilted washboard potential as often assumed. Heating effects and thermal fluctuations from the low-resistance state to a high-resistance, quasinormal regime appear to set independent upper bounds for the switching current.
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Myasnikova SE, Parshin VV, van't Klooster K, Valsecchi G. Reflectivity of antenna and mirrors reflectors at 110 and 200 GHz. In: Proc. 4th international conference on antenna theory and techniques. Vol 2.; 2003. p. 624–7.
Abstract: Reflectivity (reflection loss) investigations of nickel samples with different types of surface finish, with and without rhodium coating, have been carried out in the 110-200 GHz frequency range on an installation developed in the Applied Physics Institute of Russia. The reflectivity measurements of high quality silver coated and gold coated mirrors are also presented. The reflectivity (reflection loss) investigations of some carbon fibre samples with and without aluminium coating have been made. Results are interesting, in view of the anisotropy of the carbon fibre material.
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van't Klooster CGM, Parshin VV, Myasnikova SE. Reflectivity of antenna reflectors: measurements at frequencies between 110 and 200 GHz. In: Proc. Antennas and propagation society international symposium. Vol 3.; 2003. p. 528–31.
Abstract: It is imperative to test the mechanical, electrical and thermal-optical properties of MM and sub-MM reflector antennas. Electrical, thermal and optical properties are very important and high-accurate measurements lead, obviously, to more accurate results in applications. This paper deals with measurement of electrical reflectivity in the range 110-200 GHz. Reflectivity has been measured for a number of samples, which represent materials used in reflector antennas. Both metal samples and carbon-fibre samples were tested in a dedicated facility available for this purpose at the Applied Physics Institute in Nizhny Novgorod (IAP). The test facility is shortly discussed, with techniques for data extraction. Calibration is done with high quality silver coated mirrors and aluminium control samples. Accurate results have been derived with indicative interesting results.
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Baubert J, Salez M, Delorme Y, Pons P, Goltsman G, Merkel H, et al. Membrane-based HEB mixer for THz applications. In: Chiao J-C, Varadan VK, Cané C, editors. Proc. SPIE. Vol 5116. SPIE; 2003. p. 551–62.
Abstract: We report in this paper a new concept for 2.7 THz superconducting Niobium nitride (NbN) Hot-Electron Bolometer mixer (HEB). The membrane process was developped for space telecommnunication applications a few years ago and the HEB mixer concept is now considered as the best choice for low-noise submillimeter-wave frequency heterodyne receivers. The idea is then to join these two technologies. The novel fabrication scheme is to fabricate a NbN HEB mixer on a 1 μm thick stress-less Si3N4/SiO2 membrane. This seems to present numerous improvements concerning : use at higher RF frequencies, power coupling efficiency, HEB mixer sensitivity, noise temperature, and space applications. This work is to be continued within the framework of an ESA TRP project, a 2.7 THz heterodyne camera with numerous applications including a SOFIA airborne receiver. This paper presents the whole fabrication process, the validation tests and preliminary results. Membrane-based HEB mixer theory is currently being investigated and further tests such as heterodyne and Fourier transform spectrometry measurement are planed shortly.
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Yagoubov PL, Hoogeveen RWM, Maurellis AM, Mair U, Krocka M, Wagner G, et al. TELIS — development of a new balloon borne THz/submm heterodyne limb sounder. In: Proc. 14th Int. Symp. Space Terahertz Technol.; 2003. p. 204–14.
Abstract: We present a design concept for a new state-of-the-art balloon borne atmospheric monitor that will allow enhanced limb sounding of the Earth's atmosphere within the submillimeter and far-infrared wavelength spectral range: TELIS, TErahertz and submm LImb Sounder. The instrument is being developed by a consortium of major European institutes that includes the Space Research Organisation of the Netherlands (SRON), the Rutherford Appleton Laboratory (RAL) in the United Kingdom and the Deutschen Zentrum far Luft- und Raumfahrt (DLR) in Germany (lead institute). TELIS will utilise state-of-the-art superconducting heterodyne technology and is designed to be a compact, lightweight instrument capable of providing broad spectral coverage, high spectral resolution and long flight duration (-24 hours duration during a single flight campaign). The combination of high sensitivity and extensive flight duration will allow evaluation of the diurnal variation of key atmospheric constituents such as OH, HO,, C10, BrO together will longer lived constituents such as 0 3 , HCL and N 2 0. Furthermore, TELIS will share a common balloon platform to that of the MIPAS-B Fourier Transform Spectrometer, developed by the Institute of Meteorology and Climate research of the University of Karlsruhe, Germany. MIPAS-B will provide simultaneous and complementary spectral measurements over an extended spectral range. The combination of the TELIS and MIPAS instruments will provide atmospheric scientists with a very powerful observational tool. TELIS will serve as a testbed for new cryogenic heterodyne detection techniques, and as such it will act as a prelude to future spacebome instruments planned by the European Space Agency (ESA).
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InSb detectors technical data sheet.; 2003.
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Kostiuk T. Heterodyne spectroscopy in the thermal infrared region: a window on physics and chemistry. In: University of Maryland Inn and Conference Center, editor. Proc. International Thermal Detectors Workshop (TDW'03), session 7 (Heterodyne detectors). 3501 University Boulevar East Adelphi, MD 20783; 2003.
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Гольцман ГН, Лудков ДН. Сверхпроводниковые смесители на горячих электронах терагерцового диапазона и их применение в радиоастрономии. Изв. высших учебных заведений. Радиофизика. 2003;46(8/9).
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