Ultra high speed graphene optical modulator design based on tight field confinement in a slot waveguide
We present a design of an ultra fast in line graphene optical modulator on a silicon waveguide with a bandwidth exceeding 100 GHz, very small power consumption below 15 fJ/bit, and insertion loss of 1.5 dB. This is achieved by utilizing the transverse electric mode silicon slot to tailor the overlap of graphene electrodes, thus significantly reducing the capacitance of the device while maintaining a low insertion loss and using conservative estimates of the graphene resistance. Our design is substantiated by comprehensive finite element method simulations and RC circuit characterization, as well as fabrication feasibility discussion.