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Comparison of Geometrical Factors of Dielectric Resonators Prepared for the Surface Resistance of Superconductor Films: Field Analysis vs. Computer Simulation

Yang, Woo-Il (Department of Physics and Center for Wireless Transmission Technology, Konkuk University)
Jung, Ho-Sang (Department of Physics and Center for Wireless Transmission Technology, Konkuk University)
Kim, Myung-Su (Department of Physics and Center for Wireless Transmission Technology, Konkuk University)
Cho, Man-Soon (Korea Atomic Energy Research Instititute)
Choo, Kee-Nam (Korea Atomic Energy Research Instititute)
Lee, Sang-Young (Department of Physics and Center for Wireless Transmission Technology, Konkuk University)

Publication Information

Progress in Superconductivity / v.13, no.2, 2011 , pp. 97-104 More about this Journal

Abstract

In the dielectric resonator method, which has been widely used for measuring the microwave surface resistance of superconductors, accuracies in the geometrical factors (G-factors) affect the uncertainty in the measured surface resistance. We compare the G-factors of short-ended sapphire resonator as obtained by using field analysis with those by using computer simulations: The former is obtained by using the analytic expressions for the electric and the magnetic field components inside the resonator, and the latter by using computer software. The G-factors as obtained by using the latter appear to be closer to those obtained by using the former as the resonator space is divided into larger number of sub-space, i.e., a tighter mesh, with a difference of ~8 % observed for a mesh of 14400 sub-spaces reduced to ~2 % for 114996 sub-spaces. Variations in the relative uncertainty in the surface resistance of typical $YBa_2Cu_3O_{7-\delta}$ superconductor films with those in the G-factors are studied, which provides an upper limit of the relative uncertainty in the G-factors required for realizing the target uncertainty in the surface resistance. These results could be useful in estimating the optimum number of meshes for obtaining the G-factors through computer simulations.

Keywords

Microwave surface resistance; dielectric resonator; geometrical factor; superconductor film; uncertainty;

Citations & Related Records

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