HIGH T_C SUPERCONDUCTING ELECTROMAGNETIC WAVE DETECTORS FOR MILLIMETER AND SUBMILLIMETER BANDS USING SILICON SUBSTRATES

使用硅衬底的毫米波和亚毫米波带高温超导电磁波探测器

基本信息

批准号：
07555410
负责人：
NAKAJIMA Kensuke
金额：
$ 3.84万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

项目摘要

It is expected that high Tc superconducting millimeter and submillimeter wave devices such as a low loss transmission line and a high sensitivity detector, which can be operated with a simple cryogenic system, are applicable for a ultra high speed communication system in order to supply a communication demand. Specific high frequency properties of high T_C superconductors caused by the characteristic layred structure is also attractive from the application point of view. In this research project we aimed to develop fundamental technologies of electromagnetic wave detectors for millimeter and submillimeter bands using high T_C superconducting YBCO grain boundary Josephson junctions (GBJJ) on silicon bicrystal substrates. We have first succeeded a video detection of 2.525THz signal using YBCO GBJJs operated at 70K as a result of improvements of junction parameters such as the supercondcuting transition temperature, Tc and the I_CR_N product. Furthermore, we found that high frequency response (Shapiro step) was enhanced by a weak magnetic field application for wide frequency range up to submillimeter wave through microwave. This is a quite useful knowledge to develop a practical submillimater wave spectrometer using the GBJJ.Harmonic heterodyne mixing experiments were also performed using GBJJ for a submillimeter signal of f_S=2.525THz and a microwave signal of f_<LO>=19.4176268GHz then we had 130th harmonic mixing output {IF (Intermediate Frequency) output}. For the harmonic mixing we had the signal and noise ratio (S/N) of about 20dB and the spectrum resolution of 100KHz. The S/N would be improved to some extent by optimizing high frequency circuit design. In conclusion we have substantiated that the harmonic heterodyne mixing using GBJJs performs the high spectrum resolution for millimater and submillimeter waves and a precise spectrometer for the entire frequency range will be practical together with the video detection.

预计高TC超导毫米和亚毫升波浪设备，例如低损耗传输线和高灵敏度检测器，可以使用简单的低温系统进行操作，适用于超高速通信系统，以提供通信需求。从应用的角度来看，由特征铺设结构引起的高T_C超导体的特定高频性能也很有吸引力。在该研究项目中，我们旨在使用高T_C超导YBCO晶粒边界约瑟夫森连接（GBJJ）在硅双晶底物上开发用于毫米和亚毫米频带的电磁波检测器的基本技术。我们首先使用YBCO GBJJS在70K下操作的2.525THz信号的视频检测，这是由于连接参数的改进，例如超标过渡温度，TC和I_CR_N产品。此外，我们发现，通过微波炉通过微波炉，高频响应（Shapiro步骤）通过较弱的磁场应用到亚毫米波。 This is a quite useful knowledge to develop a practical submillimater wave spectrometer using the GBJJ.Harmonic heterodyne mixing experiments were also performed using GBJJ for a submillimeter signal of f_S=2.525THz and a microwave signal of f_<LO>=19.4176268GHz then we had 130th harmonic mixing output {IF (Intermediate Frequency) output}.对于谐波混合，我们的信号和噪声比（S/N）约为20dB，频谱分辨率为100kHz。通过优化高频电路设计，将在某种程度上改进S/N。总而言之，我们已经证实，使用GBJJS的谐波杂种混合对毫米和亚毫升波的高光谱分辨率以及整个频率范围的精确光谱仪将与视频检测一起实用。