title: Compact antenna for efficient and unidirectional launching and decoupling of surface plasmons.
abstract: Controlling the launching efficiencies and the directionality of surface plasmon polaritons (SPPs) and their decoupling to freely propagating light is a major goal for the development of plasmonic devices and systems. Here, we report on the design and experimental observation of a highly efficient unidirectional surface plasmon launcher composed of eleven subwavelength grooves, each with a distinct depth and width. Our observations show that, under normal illumination by a focused Gaussian beam, unidirectional SPP launching with an efficiency of at least 52% is achieved experimentally with a compact device of total length smaller than 8 μm. Reciprocally, we report that the same device can efficiently convert SPPs into a highly directive light beam emanating perpendicularly to the sample.
authors: Laboratoire Charles Fabry, Institut d'Optique, Univ Paris-Sud, CNRS, Campus Polytechnique RD 128, 91127 Palaiseau cedex, France.
authors: Alexandre
authors: A
authors: Baron
authors: Eloïse
authors: E
authors: Devaux
authors: Jean-Claude
authors: JC
authors: Rodier
authors: Jean-Paul
authors: JP
authors: Hugonin
authors: Emmanuel
authors: E
authors: Rousseau
authors: Cyriaque
authors: C
authors: Genet
authors: Thomas W
authors: TW
authors: Ebbesen
authors: Philippe
authors: P
authors: Lalanne