In-plane electric field confinement engineering in graphene-based hybrid plasmonic waveguides.

Surface plasmon polaritons (SPPs) are surface modes confined to metal-dielectric interfaces. This confinement enhances the electromagnetic field and therefore, SPPs are sensitive to surface conditions. The properties of two dimensional materials such as graphene thus can be enhanced and used to engineer nanoscale components for optical communications. However, SPPs are transverse magnetic modes with electric fields out-of-plane that limit flexibility. In this contribution, we numerically analyze the confinement and in-plane enhancement in graphene-based hybrid plasmonic waveguides. We find that plasmonic modes supported by metal nanoparticle chain waveguides provide higher in-plane enhancement compared to those supported by nano-strip and slot hybrid plasmonic waveguides. Our results contribute to the performance improvement of graphene light absorption devices, including electro-optic modulators and photodetectors.