A flexible procedure to avoid the boundary materials singularities in 2D transformation-based cloaks

摘要： An out-of-plane coordinate transformation can avoid singular materials in a two-dimensional electromagnetic cloak. Based on numerical simulations of elliptical cylinders, in this paper we show that the use of two different constants to define the out-of-plane stretching can result in anisotropic materials with lower values and yet with a better scattering reduction for a given incident wave direction.