Plasmon coupling effect on propagation of surface plasmon polaritons at a continuous metal/dielectric interface

The resonant coupling of surface and bulk plasmons that occurs inside the transition layer between a metal and a dielectric significantly modifies waveguiding properties of metallic nanostructures. In particular, it heavily affects the propagation of the surface plasmon polaritons maintained by a metal/dielectric interface. It is demonstrated that a great part of the energy guided by the surface plasmon polaritons is transmitted through this resonance to the bulk plasmons of the transition layer. The related damping of the surface polaritons is shown to be comparable to, or even higher than, the collisional attenuation. Thus, the plasmon coupling is predicted to play a key role for a range of plasmonic applications based on surface polaritons and their propagation in metallic nanostructures.