Cloaking from surface plasmon polaritons by a circular array of point scatterers

In recent years it has been demonstrated both theoretically and experimentally that it is possible to cloak a predefined region of space from interaction with external volume electromagnetic waves, rendering an arbitrary object inside this region invisible to an outside observer. The several strategies that have been developed for achieving such cloaking cannot be applied directly to the cloaking of a surface feature from surface plasmon polaritons propagating on that surface. Here we demonstrate that it is possible to generate an arrangement of two concentric rings of point scatterers on a metal surface that significantly reduces the scattering of surface plasmon polaritons from an object enclosed within this circular structure.