Oral contribution 1 Controlling the phase and amplitude of plasmon sources at a subwavelength scale

Surface plasmons polaritons (SPPs) are collective excitations of electrons coupled to an electromagnetic field at the interface between a dielectric and a metal [1]. Their evanescent nature along the normal to the metal/dielectric interface allows a subwavelength confinement that can be significantly smaller than diffraction limited optical waves in bulk media. SPPs, therefore, are ideal candidates for the construction of subwavelength optical devices. In the past few years, SPPs have also been identified to be the major physical mechanism involved in the extraordinary transmission of light (ETL) through metal films with subwavelength holes which was first reported by Ebbesen et al [2]. Subsequent studies have been made on uniform periodic arrays of holes, slits, and more complex shapes fabricated in metallic films. Those studies demonstrate that one can take advantage of the interferences between plasmons generated on metal films by uniform periodic sources (e.g., slits or holes in metal films) to, for instance, focus or disperse light, or realize ETL. Naturally, for flexible control and manipulation of light by such metal films, it is necessary to evolve beyond the uniform periodic sources and introduce the rich possibilities afforded by non-uniform source.films. When light enters a subwavelength dielectric structure in a metallic film, a significant fraction