Optimizing high frequency response of thin films deposited on composite substrates

Author

Rizkalla, Maher E. ; Girgis, Girgis A. ; Holdmann, Michael M.

Author_Institution

Dept. of Electr. Eng., Purdue Univ., Indianapolis, IN, USA

Volume

27

Issue

2

fYear

1991

fDate

3/1/1991 12:00:00 AM

Firstpage

1313

Lastpage

1316

Abstract

The authors consider the thermal limitations placed on the high-frequency response of a superconducting device (switch) composed of a thin film (YBa₂Cu₃O₇) deposited on magnesium, sapphire, or silver substrates. In applying successive current pulses to the film, the heat generated during the quench must be transmitted from the film (source) through the substrate and dissipated in the coolant bath. The heat transfer from the film to the coolant medium is modeled in stages using plane wave theory. The optimum high-frequency response is obtained by matching the acoustic impedance of the multilayered structure to that of the liquid coolant (load). In general, a 20-80% improvement in the transmission coefficient for the generated heat could be gained by the addition of the matching layers

Keywords

barium compounds; high-temperature superconductors; superconducting devices; superconducting thin films; yttrium compounds; Ag; Mg; SiO₂; YBa₂Cu₃O₇; acoustic impedance; composite substrates; coolant bath; heat generated; heat transfer; high frequency response; high temperature superconductor; multilayered structure; plane wave theory; quench; superconducting device; switch; thermal limitations; thin films; Coolants; Frequency response; Magnesium; Silver; Sputtering; Substrates; Superconducting devices; Superconducting thin films; Switches; Thin film devices;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.133426

Filename

133426