All-dielectric metamaterial: a ferroelectric-based scheme in the microwave range

Dielectric metamaterials are an attractive alternative to metallic metamaterials in order to reduce losses. Mie resonances in dielectric resonators can give rise to a resonant effective permeability or permittivity at resonance frequencies. When resonances are sufficiently enhanced permeability or permittivity can become negative. In the microwave range 2D rod-shaped or 3D cylinder-shaped resonators made of high-permittivity ferroelectric material can be used to demonstrate such phenomena. In the first part we present experimental proof for TE-modes in rod resonators in the X-band (8.20-12.40GHz) using barium strontium titanate (Ba0.4Sr0.6TiO3, epsilon = 575). In the second part we present experimental proof for modes in cylinder resonators in both the X and S-band (2.60-3.95GHz) using a commercial ceramic (epsilon = 78). A negative index of refraction is shown in both cases.