Transformation of surface plasmon polaritons by surface structures

We present a new, simple, planar structure that effects the all-angle negative refraction of a surface plasmon polariton incident on it. We also predict a step-wise increase in the frequency dependence of the transmissivity of a surface plasmon polariton propagating through a slit of finite length on a planar metal surface at each frequency at which an infinitely long slit can support an additional guided wave polariton.