Hybrid plasmon polariton guiding with tight mode confinement in a V-shaped metal/dielectric groove

Plasmonic waveguides consisting of metallic grooves filled with low- and high-index dielectrics are proposed and the optical properties of guided plasmonic modes are investigated at a wavelength of 1550 nm. Numerical simulations reveal that the quasi-TE-like fundamental hybrid plasmonic mode exhibits strong localization near the low-index dielectric gap, along with pronounced local field enhancement and relatively small mode area. Moderate propagation loss can be achieved as well, corresponding to a propagation distance of around tens to hundreds of microns. The proposed hybrid plasmonic structure is compatible with the fabrication techniques of traditional channel plasmon polariton waveguides, and these structures could be employed as interesting building blocks for highly integrated photonic circuits.