Practical realization of transformation-optics designed invisibility cloak through layered structures

The idea of cloaking objects from the observation by electromagnetic (EM) fields based on the recently proposed transformation optics requires anisotropic space-dependent inhomogeneous medium to construct the cloak. To reduce the design complexity and realization difficulty, in this paper we present an approach of constructing the invisibility cloak through layered structures of isotropic homogeneous media. We will show the practical design procedure based on the effective medium theory. Two examples, one for a cylindrical cloak and the other for a ground plane cloak, will be demonstrated and the cloaking performances will be verified through full-wave EM numerical calculations. The proposed cloaks are composed of normal dielectric multilayers, thus can lead to easy experimental demonstration of non-magnetic cloak in the frequency range from microwave to optical.