John L. Volakis
The Ohio State University
Electrical and Computer Engineering Dept.
ElectroScience Laboratory
1320 Kinnear Rd., Columbus, OH 43212
Engineered materials, such as new material composites, electromagnetic bandgap and periodic structures have had strong interest in recent years due to their extraordinary and unique electromagnetic behavior. Recently, a new class of magnetic photonic crystals (MPCs) and Double Band Edge (DBE), displaying spectral nonreciprocity, were introduced. Studies of these crystals have demonstrated that MPCs exhibit the interesting phenomena of (a) drastic incoming wave slow down, coupled with (b) significant amplitude growth while (c) maintaining minimal reflection at the interface with free space. The phenomena are associated with diverging frozen modes that occur around the stationary inflection points within the band diagram. Taking advantage of the frozen mode phenomena, we demonstrate that individual antenna elements and linear or volumetric arrays embedded within the MPC and DBE structures allow for supergain effects that can lead to novel miniature array configurations. In the presentation, we discuss the theory of these materials and other related bandgap structures and metamaterials; demonstrate antenna and array performance using realistic materials; and discuss issues relating to losses, gain sensitivity and crystal geometrical parameters.