All-Dielectric Two-Dimensional Metamaterial Claddings for Evanescent Field Engineering of Quasi-TM Modes

The engineering of evanescent fields from optical waveguides can increase the density level of integrated optical devices. The replacement of an all-isotropic cladding by an all-dielectric metamaterial one provides greater control of the evanescent fields. This study investigates the performance of an all-dielectric two-dimensional metamaterial cladding in strip waveguides. The waveguide core and higher refractive index of the metamaterial cladding are composed of the same material, and for sake of numerical demonstration, Si3N4 was used as a higher refractive index embedded in SiO2 (lower refractive index). The advantages of such an approach are investigated in waveguide bends. By comparing the metamaterial cladding proposal to a conventional cladding (all-isotropic one), the quasi-TM mode presented a reduction of about 61.5% of bending loss per 180° turn.