Parameter design of cylindrical invisible cloak applied nonlinear transformation

A methodology to control electromagnetic fields based on coordinate transformation was put forth by Pendry et al. Through space transformation the permeability and permittivity tensors of the invisible cloak can be obtained. The previous papers about invisible cloak mainly used the linear mapping. In this paper, we use nonlinear mapping to design invisible cloak and analyze its effect on the parameters of the cloak. Full-wave simulations are given to illustrate its effect. Through designing the proper nonlinear function, it can control the variation of constitutive parameter so that the design difficulty can be reduced.