Investigation of the separate optical nonlinear contributions of the core and cladding materials of silicon photonics slotted waveguides

The nonlinear properties of slotted silicon photonic waveguides filled with third-order nonlinear materials (NM, DDMEBT polymer) are quantitatively studied by separately calculating the effective nonlinearity susceptibilities associated to the silicon and cladding material, respectively. Optimization of the silicon slotted waveguide geometry is performed and focused on the optimization of optical power confinement in the high FOMTPA cladding material and of A(eff)(NM)/A(eff)(Si). The simulated nonlinear wave evolution results show the importance of properly choosing the silicon rail and slot widths in order to minimize the influence of the two-absorption process and associated free carrier effects (free carrier absorption, free carrier refraction).