Intersected slot waveguide for dual polarized mode low-index confinement and its polarization conversion

Intersected slot waveguide is proposed to strongly confine TE and TM modes simultaneously. Confinement factors as wells as single-mode condition are given for fully symmetrical a-Si/SiO2/SOI intersected slot waveguide and the SiN_x-covered case @ 1.55 mum. A pertinent polarization- independent device can be realized by size tuning, or by employing the analyzed polarization converter to alternatively treat the polarized modes. The conversion efficiency is also investigated in size dependence by mode matching method.