Design of isotropic 3-D multilayered CRLH metamaterial structures using conductive mesh plates and dielectric resonators

Almost isotropic three-dimensional multilayered composite right/left handed metamaterial structure is proposed and designed. It is composed of conductive mesh plates and dielectric layers including dielectric resonators with high dielectric constant. Basically, the structure has uniaxial anisotropy. The polarization of incident waves is restricted to directions parallel to the stacked layers. The numerical results show that not only the wavenumber vector but also wave impedance of the designed structures provides almost isotropic characteristics in a specific frequency region. A flat lens based on the metamaterial structure was fabricated for demonstration of the negative-refractive-index structure, and beam focusing was confirmed.