Extraordinary optical transmission without plasmons: the s-polarization case

It is shown that extraordinary optical transmission through perforated metallic films is possible for s-polarization. Although surface plasmons do not exist for this polarization, their role can be played by a wave sustained by a thin dielectric layer on top of the metallic film. The numerical simulations presented here confirm that the existence of a surface wave, whatever its nature, is responsible for the extraordinary optical transmission phenomenon.