Advances of Computational Efficiency and Characterizations of Metamaterials: Tribute to Brilliant Contributions in Wave Interaction with Complex Media

Many have used equivalent representation of metamaterials with isotropic or anisotropic media. Analyses were basically based on matching measured or calculated scattering parameters of metamaterial design with those of a material slab with, in general, 18 terms permittivity and permeability tensors were developed for the equivalent material representation. The objective is to provide better understanding of the propagation and scattering characteristics of the metamaterial designs, based on fundamental wave materials interaction, and to examine avenues for achieving advanced characteristics, e.g., broader band, enhanced absorbability, improved focus efficiency, etc. With the continued advances in metamaterials designs, many unintuitively and dimensionally multiscale configurations were reported and many hours if not days of computational time were required to develop these designs. This brings additional benefits of the equivalent material representation of complex, and intuitively difficult to explain metamaterial structures, and the use of fundamentally established concepts of wave interaction with complex media, to help improve computational efficiency in optimizing the characteristics, in addition to providing critically needed fundamental understanding of the achieved results. This is where we believe Professor Ishimaru's foundational work on wave propagation in random and complex mediums will play a key role.