High Confinement Factor Ridge Slot Waveguide for Optical Sensing

A ridge slot waveguide on 220 nm silicon-on-insulator platform is proposed and theoretically investigated. The confinement factor of the ridge slot waveguide is much higher than the fully etched slot waveguide in the case of air-cladding. The sensitivity of sensors based on ridge slot waveguides is higher than that of the fully etched slot waveguides when the cladding refractive index is in the range of 1.0-1.18.