Development of high-temperature superconducting filters operating at temperatures above 90 K

• Published in: Chinese science bulletin Vol. 54; no. 19; pp. 3596 - 3599
• Main Authors: Xia, HouHai, Zhou, ChunXia, Zuo, Tao, He, Ming, Ji, Lu, Zhou, TieGe, Zhao, XinJie, Fang, Lan, Yan, ShaoLin
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Science in China Press 01.10.2009
• Subjects: Articles/Automatic Control Technology; Chemistry/Food Science; Earth Sciences; Engineering; HTS; Humanities and Social Sciences; Life Sciences; multidisciplinary; Physics; Science; Science (multidisciplinary); 低温物理学; Tl; thin film; HTS filter; characteristics at different temperatures; Ba; CaCu; O
• ISSN: 1001-6538; 2095-9273; 1861-9541; 2095-9281
• DOI: 10.1007/s11434-009-0347-4

This paper represents the development of a high temperature superconducting （HTS） filter, the highest operating temperature of which is up to 93 K. The filter is designed for S band with 4% fractional bandwidth and fabricated using thallium-barium-calcium-copper oxide （TI2Ba2CaCu2O8） thin films. At 93 K, the measurements of the filter show that the insertion loss in the passband is less than 0.22 dB, the return loss is better than 20 dB, and the out-of-band rejection is more than 80 dB. The analysis on the characteristics of the filter operating at different temperatures shows that the filter can work well at temperatures around 90 K. The temperature of 93 K is the highest among the previous reports for HTS filters. The result reported in this paper is significant for HTS filters to be used in the field of microwave communication requiring high sensitivity.