Theoretical analysis of the surface wave along a metal-dielectric interface

The metal-dielectric interface supports surface plasmons. But the metal-dielectric interface with defects has not only surface plasmons but also residual waves. In this paper we calculate the fields along the metal-dielectric interface with defects from Maxwell's equations analytically using the surface impedance approximation and study the asymptotic behavior of the residual waves. These analytic results set up a solid foundation to understand various phenomena such as beaming and extraordinary optical transmission.