An all-optical modulator based on a graphene–plasmonic slot waveguide at 1550 nm

An all-optical modulator with high modulation efficiency based on a graphene-plasmonic slot waveguide structure is proposed. The modulation efficiency is enhanced by the strong interaction between the light and the graphene?plasmonic structure. A modulation efficiency of 0.21?dB??m?1 is obtained with the signal light at a wavelength of 1550 nm. A graphene?plasmonic slot waveguide device of length of 10 ?m is fabricated in the experiment. Benefiting from the strong modulation, it is a promising candidate as an on-chip optical modulator with high modulation efficiency and micrometer-scale footprint.