高温超导本征约瑟夫森结阵列亚太赫兹辐射信号探测研究

Terahertz/Subterahertz technology has a great of important applications, such as telecommunication, outer-space exploration, national security, medical imaging, etc. Due to the lack of effective methods to generate and detect subterahertz wave, the research in the Sub-THz band is very limited and remain relatively unexplored. Recently, many researcher groups have attached importance to the subterahertz source based on high temperature superconducting intrinsic Josephson junction array due to its high performance.It will be studied in this project that the key technologies of generating and detecting subterahertz radiation based on high temperature superconducting intrinsic Josephson junction array. Including:①studying on the mechanism of ultra-high frequency electromagnetic oscillation and radiation in high temperature superconducting intrinsic Josephson junction array, which will provide theoretical guidance to increase the output power from the intrinsic junction array in the subterahertz band;② studying on the fabrication process of high temperature superconducting intrinsic Josephson junction array and the effective methods for achieving stable phase locking between each single junction;③studying on the effective methods to improve the electromagnetic coupling intensity between high temperature superconducting intrinsic Josephson junction array and the free space. The practical subterahertz source based on high temperature superconducting intrinsic Josephson junction array is expecting to be developed in this project, which may lead to fill the Terahertz gap.

太赫兹/亚太赫兹技术在信息通信、深空探测、国家安全和医学成像等事关国计民生的诸多领域中都具有非常重要的应用价值。但长期以来，由于缺乏产生和检测亚太赫兹波的有效方法，使得该波段电磁波的应用成为空白。由于超导约瑟夫森结器件是一种特性优良的高频波信号源，因此基于高温超导本征约瑟夫森结阵列的亚太赫兹波信号源的研究正引起广泛的重视。本课题拟研究高温超导本征约瑟夫森结阵列亚太赫兹信号产生及其探测的关键技术。主要内容有：①研究高温超导本征约瑟夫森结阵列超高频电磁振荡和辐射的机制，为提高本征结阵列亚太赫兹辐射信号的输出功率提供理论指导；②研究高温超导本征约瑟夫森结阵列的制备工艺和实现稳定相位锁定的有效方法：③研究提高本征约瑟夫森结阵列亚太赫兹辐射信号耦合输出功率的有效方法和途径。通过对该课题的深入研究，争取研制出基于高温超导本征约瑟夫森结阵列的实用的亚太赫兹波信号源，以填补该波段电磁应用的空白。

太赫兹/亚太赫兹技术在信息通信、深空探测、国家安全和医学成像等事关国计民生的诸多领域中都具有非常重要的应用价值。但长期以来，由于缺乏产生和检测亚太赫兹波的有效方法，使得该波段电磁波的应用成为空白。由于超导约瑟夫森结器件是一种特性优良的高频波信号源，因此基于高温超导本征约瑟夫森结阵列的亚太赫兹波信号源的研究正引起广泛的重视。. 本课题自立项以来，在课题组老师和同学的共同努力下，在研究高温超导本征约瑟夫森结阵列亚太赫兹电磁信号的产生及其探测的关键技术方面取得了一些进展和突破。主要研究成果有：①用化学方法制备Tl-2212 高温超导薄膜取得了突破。采用溶胶-凝胶法制备的Tl-2212高温超导薄膜，其临界温度达到106 K, 在77 K、 0 T条件下其临界电流密度为0.83 mA/cm2；②组建了一套本征约瑟夫森结器件亚太赫兹波辐射信号检测系统，其测量精度可达纳瓦量级；③研究了串联双晶约瑟夫森结阵列的毫米波特性。在78.6Ｋ温度下，测量了由644个双晶约瑟夫森结组成的串联结阵列的毫米波辐射特性，得到辐射峰的中心频率为69.3GHz，检测到的辐射功率约为20pW；④研究了Tl-2212本征约瑟夫森结阵列的毫米波特性，检测到本征结阵列的非相干自辐射信号。这些成果的取得为今后进一步研究超导电子学器件特性及其应用打下良好的基础。