Natural Oscillations of Isolated Dielectric Resonators

Important parameters of dielectric resonators (DR) are the characteristics of their natural oscillations: resonant frequencies, partial quality factors, field distributions. This chapter discusses the natural oscillations of isolated dielectric resonators in open space. The frequency spectrum and fields of spherical, cylindrical and rectangular resonators are examined in detail. The main attention is paid to the lower types of natural oscillations, as well as high-quality oscillations of higher types—whispering gallery modes (WGM). Using the example of a spherical DR, the influence of dielectric and metallic inhomogeneities on frequencies and quality factors was studied.