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The electromagnetic (EM) properties of shielded gyromagnetic spheres are characterized with the aid of an electrodynamic model formulated for the transverse electric (TE) modes of an isotropic sphere, in a similar way as dielectric resonators are commonly analyzed. Broadband characteristics of geometric and energy filling factors are presented. A new measure of the magnetic loss tangent is introduced which is positive despite the intrinsic permeability of the gyromagnetic medium being negative, where existing definitions yield a non-physical negative value. The sample size dependence of those quantities is also assessed. The conclusions from the analysis are applied to investigate and de-embed ferromagnetic linewidth errors which can occur in broadband measurements of magnetic garnet spheres. Magnetic anisotropy fields and the gyromagnetic $g$ -factor are also estimated from the measurement data. Experiments were performed in a two-port subwavelength cavity, covering a frequency range of up to 28 GHz. Additionally, two-port rectangular resonant cavity linewidth measurements at a few modes have been conducted. Good agreement between the two methods is found if the systematic error is accounted for. [ABSTRACT FROM AUTHOR]

A method that allows the determination of magnetic permeability in magnetic bodies, as well as the ferromagnetic resonance (FMR) linewidth, by measuring only the quality factor and the resonant frequency of the perturbed microwave cavity at FMR is presented. The method is based on a set of equations derived for various types of magnetic media, including ferrites, single crystals, and polycrystalline materials. The evaluation of resonators containing magnetic medium is considered, and a detailed description of the spectrometer and the experimental procedure are presented. Independently measured yttrium iron garnet samples were used to validate the method. [ABSTRACT FROM PUBLISHER]

The aim of this paper is the analysis of the multipactor effect in a parallel-plate waveguide when a ferrite slab, transversally magnetized by a static magnetic field parallel to the waveguide walls, is present. Employing an in-house developed code, numerical simulations are performed to predict the multipactor radio frequency voltage threshold in such a ferrite-loaded waveguide. Variations of the ferrite magnetization field strength and the ferrite slab height are analyzed. Effective electron trajectories are also shown for a better understanding of the breakdown phenomenon, finding different multipactor regimes. [ABSTRACT FROM AUTHOR]