Silicon-on-Insulator Polarization Rotator Based on a Symmetry Breaking Silicon Overlay

We demonstrate a polarization rotator fabricated using a 4 etch-step complementary metal-oxide-semiconductor (CMOS)-compatible process including layer depositions on a silicon-on-insulator wafer. The measured polarization rotation efficiency is over a wavelength range of 80 nm. A robustness investigation shows that the design is compatible with CMOS fabrication capabilities.