The effect of superconducting ground plane on microwave characteristics of unpatterned superconducting films in the mixed state

Chien Jang Wu, M. H. Tsai, H. D. Yang, Yu Sheng Tsai

Research output: Contribution to journalArticle


The microwave characteristics of a multilayer structure made of a type-II superconducting thin film and a dielectric substrate together with a superconducting ground plane is studied theoretically by using the model of the self-consistent treatment of vortex dynamics. The dependence of reflection coefficient on the temperature and static magnetic field is reduced owing to the existence of the superconducting ground plane, especially at temperatures near Tc and at higher fields. Comparison of the interesting oscillation phenomenon in the associated effective surface resistance between the Meissner state (b - 0) and mixed state (b ≠ 0) is made. We find that the superconducting ground plane not only strongly narrows down the resonant peak shape but also enhances the peak height. Finally, a similar layered structure made of a superconducting thin film on a dielectric substrate shielded by a buffer layer is also considered. We specifically demonstrate that the buffer layer has essentially no substantial influence on microwave reflectance, transmittance, and complex surface impedance. The role played by the buffer layer is in great contrast to that in a planar transmission line.

Original languageEnglish
Pages (from-to)192-202
Number of pages11
JournalIEEE Transactions on Applied Superconductivity
Issue number4
Publication statusPublished - 1998 Dec 1



  • Microwave
  • Mixed state
  • Multilayer
  • Superconducting films

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

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