Regular papers

Polarization conversion with a photonic crystal slab

¹ Laboratoire Charles Fabry de l’Institut d’Optique, CNRS, Université Paris-Sud, Campus Polytechnique, RD128, 91127 Palaiseau, France
² Laboratoire d’Optique Physique, LPEM UPR5 CNRS, Ecole Supérieure de Physique et Chimie Industrielles, 10, rue Vauquelin, 75005 Paris, France
³ Laboratoire de Physique du Solide, University of Namur (FUNDP), 61 rue de Bruxelles, 5000 Namur, Belgium

^* marine.laroche@institutoptique.fr

Received: 14 October 2008

Abstract

We show that a photonic crystal slab can enable efficient polarization conversion. Two mechanisms are identified. The first mechanism relies on the anisotropy of the bulk properties of the metamaterial and is mediated by interferences. The second mechanism is due to the resonant excitation of leaky surface waves at the interface of the photonic crystal. The latter is analogous to the polarization conversion by excitation of surface plasmons on a metallic grating. This is another example of the possibility of mimicking plasmonics with photonic crystals.