Graphene-Assisted Electroabsorption Optical Modulator Using D-Microfiber

We report on an electroabsorption optical modulator using graphene-on-D-microfiber configuration. Two-lamellae of graphene embedded in the dielectric spacer are incorporated with a side-polished microfiber to enhance the graphene-light interaction efficiency measured in terms of effective mode index change. The effects of the side-polished microfiber on different radial distances are analyzed on an effective mode index change and energy flow through the fiber for transverse electric mode by applying bias to the graphene lamellae. The theoretical simulated results show that the effective mode index change is maximized from a value of 0.006 to 0.018, which is almost three times larger than the existing fiber optic modulator. Calculations also show that the electroabsorption optical modulator can be realized with extinction ratio as high as 17.80 dB, modulation bandwidth of 97.26 GHz and operates at C-band of optical communication with the active length of 80 μm long at the expense of 24.30 fJ/bit.