Graphene plasmonic waveguide based on a high-index dielectric wedge for compact photonic integration

A novel waveguide consisting of a uniformly biased graphene placed above a high-index dielectric triangular wedge is proposed and analyzed theoretically. The combination of graphene plamonics and slot effect results in both the tight confinement and low loss. Superior to the previous studied graphene ribbon waveguides, the new design is easy to fabricate and supports single mode transmission. Studies on the crosstalk between adjacent waveguides reveal the ability to increase the integration density by ∼2 times compared with the traditional metal-insulator-metal slot waveguide. The proposed waveguide could be an interesting alternative to realize high density photonic circuits at terahertz and far-infrared regime.