中国物理B ›› 2021, Vol. 30 ›› Issue (5): 58503-058503.doi: 10.1088/1674-1056/abd7e1
Ming-En Tian(田明恩)1, Zhi-He Long(龙之河)2, You Lan(蓝友)1, Lei-Lei He(贺磊磊)1, and Tian-Liang Zhang(张天良)1,†
Ming-En Tian(田明恩)1, Zhi-He Long(龙之河)2, You Lan(蓝友)1, Lei-Lei He(贺磊磊)1, and Tian-Liang Zhang(张天良)1,†
摘要: A single-stage ring resonator capable of introducing six modes within the ultra-wideband (UWB) passband is presented. The sextuple-mode resonator consists of three rings and three sets of stepped-impedance open stubs. Based on this sextuple-mode resonator, a UWB filter fed by the interdigital-coupling line (ICL) is designed. And we propose a two-round interpolation method to obtain the filter's initial dimensions. The designed filter is fabricated on a double-sided YBCO/MgO/YBCO high-temperature superconducting (HTS) thin film for demonstration. The experimental results show that this UWB filter produces eight resonances in the passband eventually, which effectively improves the in-band reflection and the band-edge steepness. Moreover, the upper stopband performance is enhanced due to the transmission zeros (TZs) generated by the stepped-impedance open stubs and the ICL structure. The measured good performance verifies the practicability of the two-round interpolation approach, which can also be extended to other odd-even-mode filter designs.
中图分类号: (Superconducting devices)