The effective permittivity of the coated ellipsoid: a tunable electromagnetic parameter approach

Permittivity and permeability are the most important electromagnetic parameters in the research of metamaterials. In this paper, an analytical method is adopted to get the effective permittivity of the coated ellipsoid. Then, the change tendencies of the effective permittivity are studied when the dimensions and the constitutive materials of the coated ellipsoid are changing, and the approximate results for different materials are derived, which can be applied in designing various devices with desired electromagnetic properties. Based on the solved effective permittivity, a focus lens composed of the coated ellipsoid is simulated in the electromagnetic simulation software HFSS and the simulation result demonstrates the accuracy of the deduced expression.