Confinement and optical properties of the plasmonic inverse-rib waveguide

Henri Benisty (1) , Mondher Besbes (1)

1 Laboratoire Charles Fabry / Naphel

Plasmonic inverse-rib optical waveguides, consisting of a high-index inverse rib embedded in low-index medium above a flat metallic surface, are investigated under four aspects: (i) the optimal angle θ of the rib sidewall for tight modal confinement is assessed, (ii) the effect of the geometric parameters and the wavelength on propagation losses is given, (iii) we use a 3D simulation to assess how well light from an emitting dipole is captured by such a tightly guiding structure, and (iv) we show that for two such parallel hybrid waveguiding systems, when one of them has added gain, we have a plasmonic version of the PT-symmetric waveguide arrangement, and we additionally show that complex gain is needed to restore a truly exceptional point in its propagation constant evolution.

Domaines: Optique [physics.optics]

Henri Benisty, Mondher Besbes. Confinement and optical properties of the plasmonic inverse-rib waveguide. Journal of the Optical Society of America B, 2012, 29 (4), pp.818-826. ⟨hal-00683901⟩