Abstract

Dielectric metamaterials (DMM) can offer polarization-independent isotropic properties and reduction of absorption due to Ohmic losses present in spit-ring-based metamaterials. For these reasons, DMMs have attracted much attention recently [1,2]. A sub-wavelength size dielectric resonator made of a high-permittivity dielectric material, such as TiO₂ (ε≈100 at 1 THz), is a key element for DMMs. Effective negative magnetic response (μ<0) in principle can be realized in a TiO₂ micro-sphere due to the first Mie resonance [2,3]. TiO₂ spheres can be synthesized in a variety of sizes, crystallinity and porosity. However characterization of these building blocks for DMMs at THz frequencies remains a serious challenge and their intrinsic resonant properties are not well-known.

© 2015 IEEE