Electromagnetic Invisibility of Elliptic Cylinder Cloaks

Structures with unique electromagnetic properties are designed based on the approach of spatial coordinate transformations of Maxwell's equations. Thisapproach is applied to scheme out invisible elliptic cylinder cloaks, which provide more feasibility for cloaking arbitrarily shaped objects. The transformation expressions for the anisotropic material parameters and the field distribution are derived. The cloaking performances of ideal and lossy elliptic cylinder cloaks are investigated by finite element simulations. It is found that the cloaking performance will degrade in the forward direction withincreasing loss.