The study of few-layer graphene based Mach−Zehnder modulator

The investigation of few-layer graphene embedded in silicon waveguide (GESW) exhibits it has a superior performance than monolayer GESW where the effective mode index variation (ΔneffΔneff) at the given chemical potential change and the number of graphene layers N (N  <5) shows in a linear relationship. The results from modal analysis show that the ΔneffΔneff of quadri-layer GESW can be as large as 0.047, based on which a Mach–Zehnder modulator has been proposed with the advantages of only 16.5 μm arm length, low energy consumption (8 fJ/bit), high extinction ration (31.8 dB) and small applied voltage (<1 V). Furthermore, the working temperature of the proposed modulator can span in a large range from 300 K to 400 K and the modulation performance stays almost unchanged when the input wavelength varies from 1520 nm to 1580 nm.