Study of mechanically tunable superconducting microwave filter using lumped elements

• Published in: IEEE transactions on applied superconductivity Vol. 13; no. 2; pp. 720 - 723
• Main Authors: Hontsu, S., Mine, S., Nishikawa, H., Nakamori, M., Fujimaki, A., Inoue, M., Maehara, A., Kawai, T.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2003; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Band pass filters; Capacitors; Chebyshev approximation; Circuit properties; Circuit simulation; Electric, optical and optoelectronic circuits; Electrical engineering. Electrical power engineering; Electronic circuits; Electronics; Exact sciences and technology; Frequency; Frequency filters; Inductors; Magnetic devices; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Microwave filters; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Superconducting filters; Superconducting microwave devices; Transformers and inductors; Tunable circuits and devices; Circuit simulation; Meander line; Chebyshev filter; Lumped parameter circuit; Inducer; High temperature superconductors; Power capacitor; Microwave filter; microwave device; tunable circuits and devices; Tunable filter; Mechanical tuning; Band rejection filter; Capacitance; Band pass filter; Superconducting filters; Simulator; Planar technology
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2003.814014

We propose a mechanically tunable superconducting microwave filter based on lumped elements composed of planar meander-line inductors (L) and inter-digital capacitors (C). As the first step, we have designed and evaluated a 3-pole Chebyshev bandpass filters with lumped elements using a circuit simulator. It is found that the center frequency, bandwidth and skirt rejection of the filter can be controlled by changing only the capacitance. The L and C elements values are estimated using an electromagnetic simulator. Furthermore, we have fabricated the inter-digital capacitor designed with the above procedure. We have evaluated change of the C values using mechanical tuning as a step toward a tunable superconducting microwave filter.