Title :
Dielectric resonators as microwave characterization tools
Author :
Moser, E.K. ; Naishadham, K.
Author_Institution :
Mater. Directorate, Wright Lab., Wright-Patterson AFB, OH, USA
fDate :
6/1/1997 12:00:00 AM
Abstract :
Dielectric resonators, formed by sandwiching a cylindrical piece of polished dielectric material (sapphire) between two planar endplates, offer an attractive platform for microwave testing of HTS films. Each resonator is tested as a two-port system, by exciting and detecting the modal fields with loop-terminated coaxial cables. The observed quality factor of the resonator is a gauge of the surface resistance of the endplates. We discuss utilization of this method as a tool for testing /spl sim/1 cm/sup 2/ areas, at frequencies in the 20-40 GHz range, and at cryogenic temperatures, using field analysis to explore trade-offs involving cylinder geometry, field confinement, and miniaturization. An improved method for analyzing two-port data eases the difficulties associated with testing the resonator in a cryogenic environment.
Keywords :
dielectric resonators; high-temperature superconductors; microwave measurement; superconducting thin films; surface conductivity; 20 to 40 GHz; HTS films; cryogenic temperature; cylinder geometry; dielectric resonators; field analysis; field confinement; loop-terminated coaxial cables; microwave testing; miniaturization; modal fields; planar endplates; quality factor; surface resistance; two-port system; Coaxial cables; Cryogenics; Dielectric materials; Frequency; High temperature superconductors; Materials testing; Q factor; Surface resistance; System testing; Temperature distribution;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
