Slot and Layer-Slot Waveguide in the Visible Spectrum

Slot waveguides based on TiO
₂
nanowires are numerically analyzed in the visible spectrum. The modal properties and the sensing capabilities of a conventional slot waveguide are investigated at an operating wavelength of 635 nm. Furthermore, a novel slot waveguide configuration called Layer-slot (L-slot) is proposed and discussed. The numerical results show that L-slot waveguides permit to achieve field confinement and sensing properties with values comparable with conventional slot waveguide, but with a strongly simplified fabrication process.