We demonstrate that the optical energy carried by a TE dielectric waveguide mode can be totally transferred into a transverse plasmon mode of a coupled metal nanoparticle chain. Experiments are performed at 1.5 μm. Mode coupling occurs through the evanescent field of the dielectric waveguide mode. Giant coupling effects are evidenced from record coupling lengths as short as ∼560 nm. This result opens the way to nanometer scale devices based on localized plasmons in photonic integrated circuits.

In this letter, we present the characterization and modeling of a metamaterial-based resonant cavity for ultrathin directive printed antennas. A planar artificial magnetic conductor is used for the two reflectors of the Fabry–Pérot-type resonant cavity. One reflector behaves as a high impedance surface, and serves as a substrate for the printed antenna. The other reflector is a partially reflective surface used as a transmitting window. The cavity is operated on subwavelength modes, the smallest cavity thickness being of the order of λ∕60. A drastic enhancement of the antenna directivity and gain is obtained over a relatively wide band from 7.5to10.1GHz, corresponding to a range of cavity thicknesses from ∼λ∕3 to ∼λ∕60. The cavity resonance is seen to be correctly predicted from the standard ray theory approach.