IEEE Transactions on Applied Superconductivity

Study of mechanically tunable superconducting microwave filter using lumped elements

Shigeki Hontsu, S. Mine, Hiroaki Nishikawa, Masaya Nakamori, Akira Fujimaki, M. Inoue, A. Maehara, T. Kawai

Published Jun 1, 2003• 14 citations

Abstract

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.

DOI: 10.1109/tasc.2003.814014

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