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41.
A novel device has been proposed which uses a double quantum well structure for the detection of signals in the THz range. The technology for the manufacturing of such devices at this point of time is significantly mature so that such a device may be easily fabricated. The detector frequency may be varied from 10 to 90 THz by changing the well widths from 10 to 30 Å. 相似文献
42.
Yiping Tang Xingguo Li Zhenfa Luo Guozhen Li 《International Journal of Infrared and Millimeter Waves》1997,18(4):827-846
This paper researches mainly the radiation characteristics of the target and detecting techniques by superconducting detector
in the submillimeter wave(SMMW) region. The calculation of transition wavelength(TW) between Planck and Rayleigh-Jeans is
given out. The experiment of detecting different targets is finished by use of superconducting detector possessing high performances.
Through the experiments in paper we can select and determine the wave bands of SMMW detecting and imaging system. The many
novel theoretical analyses and experimental results are expressed in Figs and tables of the paper. Finally, a part of calculating
results and experimental datum detected by a superconducting detector in SMMW regions are given in this paper. 相似文献
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C. L. Cates G. Briceo M. S. Sherwin K. D. Maranowski K. Campman A. C. Gossard 《Physica E: Low-dimensional Systems and Nanostructures》1998,2(1-4)
Detectors based on intersubband transitions in quantum wells have great potential for use between one and several terahertz. We propose a tunable, antenna-coupled, intersubband terahertz (TACIT) detector that is both sensitive and fast, with a speed limited only by the intersubband relaxation rate (1 ns at
at
). The detector is sensitive over a narrow range of frequencies, and the frequency of peak absorption can be tuned by applying a bias voltage to the device. 相似文献
45.
B. Roth D. Köther A. Beyer 《International Journal of Infrared and Millimeter Waves》1988,9(11):971-981
An electronical system for real-time measurement of scattering parameters of millimeterwave two-ports is described. In order to achieve a suitable measurement accuracy, the output signals of the millimeterwave detectors and the characteristic of the measurement amplifier should be matched. For this reason the detector power-characteristic is approximated by help of a polygon and it is realized with a few nonlinear amplifiers. The theoretical background and experimental results show the applicability of the measurement system presented here. 相似文献
46.
To design a new radon gas dosemeter, the knowledge of the SSNTD α counting efficiency is essential. It depends primarily on the energy and incidence angle into the detector, then on the etching conditions and finally on the track counting procedure. Therefore the elicited efficiency function represents all these factors. The detectors were exposed to α particles at different angles of incidence and energies, by using a 244Cm source; two alternative NaOH solution etching conditions were tested, 6.25 N 70°C at 6 and 12 h, respectively. The counting was performed with a light microscope, 267×, and with an automatic track analysis procedure. The critical incidence angle dependance on energy, in our standard condition (6 h), resulted θC(E)=380.0e(−0.286•(E−0.050))(1−e(−0.186•(E−0.050))), and it was used to design our new radon gas holder. 相似文献
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