Low interaction of an arbitrarily large PEC cylinder with EM waves filtered through a layered structure

The idea of diminishing the interaction between a PEC volume (however spatially extended) and the source of electromagnetic (EM) illumination is very intriguing since it constitutes the principle of operation of numerous useful devices. Cloaks, absorbers and isolators are only few of the structures whose functionalities are based on controlling the electromagnetic energy exchange of metallic scatterers with current sources. Such a feature is achieved by properly designing a layered structure made from gradually electromagnetically sparser materials which is excited by a line source. The propagation directions of the incident rays are shifted, according to Snell´s law, to be tangentially oriented to the rear boundary of the slab cluster. In this way, the EM field does not interact significantly with an arbitrarily large perfectly conducting (PEC) circular cylinder. At the same time, the reflections back to the source are not substantial due to the matched impedance of the layered structure. Accordingly, the propagated field “avoids” the PEC scatterer by cloaking it and not admitting significant energy exchange.