Development Trend of Millimeter-Wave Evaluation Techniques of Low-Loss Dielectrics and High Temperature Superconductors

Abstract

Recent development trends of several resonance methods are reviewed to measure the complex relative permittivity (relative permittivity ε_r and loss tangent tanδ of low-loss dielectric materials and the surface resistance R_s of high temperature superconductors (HTS) in microwave and millimeter-wave regions; that is, a cavity resonator method, a cut-off circular waveguide method, a balanced-type circular disc resonator method, a Fabry-Perot open resonator method, a whispering-gallery mode resonator method, a Hakki-Coleman method, a two-dielectric-resonator method, a one-dielectric-resonator method, a dielectric resonator method using NRD-guides, and a perturbation method.