Silicon-on-insulator slot waveguide design for C band optical amplification confinement

Abstract

Research in the field of photonic integrated circuits (PICs) is taking a boost, especially because of its compatibility with the modern complementary metal-oxide semiconductor fabrication technology. Silicon-on-insulator slot waveguides are a burgeoning platform for sophisticated on-chip integration applications and have been extensively leveraged for PICs. Here the structural optimization and parametric analysis of the slot waveguide geometry for optical enhancement and nanoscale confinement in the C band are presented. Theoretical investigations of the mode field distribution, field confinement factor and effective refractive index for distinct slot waveguide structures are critically examined and comprehensively evaluated. We present four types of slot waveguides, including conventional silicon-on-insulator vertical slot waveguides, slot waveguides using nitrides materials in slot regions, slot waveguides using photonic crystal slabs with air holes, and horizontal slot waveguides with aluminum nitride slots. We demonstrate that by the use of photonic crystal slabs and the presence of nitrides slots, field confinement factors can be enhanced.