A waveguide amplitude modulator based on a graphene plasmonic resonance

Abstract

Photonic waveguides with graphene can enable resonant coupling of the waveguide mode and the graphene plasmonic modes. We demonstrate theoretically that the plasmonic resonance in the hybrid waveguides can be significantly enhanced by employing a graphene nanoribbon with a deep subwavelength width when a lower-order graphene nanoribbon mode and a mode of a bare waveguide are efficiently coupled. A further increase is possible when a single graphene stripe is replaced by a finite array of graphene nanoribbons. This effect may provide a feasible platform for an efficient amplitude modulation which can be employed in the design of specific devices such as low-power modulators, filters, or sensors.