Optical switch based on Graphene clad two surface plasmonic polariton mode coupler

Abstract

Graphene exhibits both surface plasmonics and non linear optical property. Considering these properties, an optical controlled compact graphene clad surface plasmonic polariton two modes interference (GCSPPTMI) structure with silicon waveguide core has been presented for all optical switching. The cross and bar state power of the device are obtained by introducing an additional phase between the excited SPP modes in silicon coupling region through nonlinear refractive index modulation of graphene clad with incidence of very low optical pulse energy of 0.82 pJ and width of 4 ps. The coupling length of the proposed device is ∼21.6 times less than that of existing all optical switch based on SPP modes. The degradation of power imbalances of the Graphene clad SPPTMI with fabrication tolerances (±) of both width and thickness is less than that of multimode interference based nonlinear directional coupler due to having less of device parameters. Our results promise to achieve high speed and compact optical switch.