A graphene ridge nanowire hybrid surface plasma waveguide with longer transmission length

We investigated a graphene-based ridge silicon nanowire hybrid surface plasmon polariton waveguide and analyzed its modal characteristics using the finite element method software COMSOL. The waveguide is comprised of five components: a layer of graphene, ridge silicon nanowires, a silver film layer, a layer of silicon dioxide sandwiched between them, and the bottom silicon dioxide substrate, all enclosed by air. Through the optimization of the waveguide's geometric parameters, we achieved strong field confinement (ranging from λ²/100 to λ²/17) and substantial propagation distances (86-215 μm). Furthermore, to comprehensively assess the benefits of graphene rectangular hybrid waveguides, we also examined traditional rectangular hybrid waveguides. The findings demonstrate that in comparison to rectangular hybrid waveguides lacking graphene, the graphene-based waveguide we designed exhibits considerable advantages in terms of transmission length.