Scattering by planar junctions of metamaterial slabs

The aim of this work is to obtain a useful approach for evaluating the scattering by a planar junction of two lossless and isotropic double-negative metamaterial slabs illuminated at normal incidence by a plane wave. The total field at a given observation point is evaluated by summing the geometrical optics contributions and the field diffracted by the junction. With reference to the diffraction contribution, a uniform asymptotic physical optics solution expressed in terms of the transition function of the uniform theory of diffraction is here proposed. It has resulted to be efficient for compensating the geometrical optics discontinuities, easy to handle and simple to implement in a computer code.