Surface plasmon coupling on metallic film perforated by two-dimensional rectangular hole array

Christophe Sauvan (1) , Cyrille Billaudeau (2) , Stéphane Collin (2) , Nathalie Bardou (2) , Fabrice Pardo (2) , Jean-Luc Pelouard (2) , Philippe Lalanne (1)

1 Laboratoire Charles Fabry de l'Institut d'Optique / Naphel
2 LPN - Laboratoire de photonique et de nanostructures

The impact of the periodicity on the dispersion relation of surface modes supported by two dimensional (2D) structured metallic films is experimentally and numerically investigated between 1 and 5 μm. A coupling between modes propagating in two nearly orthogonal directions forming an angle of 77° is evidenced for a rectangular array of holes perforated in a gold film. The coupling results in a narrow band gap for nonzero wavevectors and in a coupled mode with a large density of states and a strong radiative damping. We show that the gap location in the (ω,k) space can be precisely tuned by changing the 2D period.

Domains: Optics / Photonic; Optics [physics.optics]

Christophe Sauvan, Cyrille Billaudeau, Stéphane Collin, Nathalie Bardou, Fabrice Pardo, et al.. Surface plasmon coupling on metallic film perforated by two-dimensional rectangular hole array. Applied Physics Letters, 2008, 92, pp.011125. ⟨10.1063/1.2830333⟩. ⟨hal-00814509⟩