ABSTRACT
Although homogeneous metamaterials have exhibited many unusual physical properties, such as negative refractions and zero-index refractions, inhomogeneous metamaterials provide a different way to control EM waves. In this chapter, we will mainly focus on the property and applications of inhomogeneous metamaterials. Inhomogeneity means that the EM parameters of the materials (e.g., the permittivity and permeability) vary with space position. The materials can be isotropic or anisotropic. Many novel devices have been proposed using inhomogeneous meta-materials, such as invisibility cloaks, concentrators, high-performance antennas, and illusion devices.
