Quasi-Optical Dielectric Resonator-Based Technique of HTS Film Millimeter-Wave Surface Resistance Measurements: Three Types of Resonators

Results of comparing advantages and disadvantages of quasi-optical dielectric resonators (QDR) of three types excited with whispering gallery modes are presented. The resonators are proposed by authors for high-temperature superconducting film surface resistance measurement in millimeter wavelength range. QDR´s are made of single crystal sapphire in the forms of cylindrical disk, truncated cone and hemisphere with a purpose of work in Ka-band. The peculiarities of resonance frequency spectra, field distribution and interaction between microwave field and the sample under test are considered. In authors´ opinion each of the resonators has own niche for application.