Surface resistance measurement of high-Tc superconductors using a microstrip ring resonator with split mode resonance

Abstract

Reported in this paper is the DC magnetic field and frequency dependence of the surface resistance of a thick-film high-Tc superconducting material measured using a microstrip ring resonator with split mode features. The mode splitting phenomenon is shown to be due to the non-uniformity of the film. The measured surface resistance follows the dependence of omega alpha B0.5, where alpha approximately=1, on frequency in the range between 900 MHz and 1800 MHz and on DC magnetic field in the range between 60 mT and 390 mT. This dependence indicates that Abrikosov fluxons distribute uniformly on the film. The linear frequency dependence, instead of omega 0.5, is understood to be due to the inhomogeneity of the film.