Silicon-on-insulator (SOI) technology is a promising platform for photonic applications with low-cost and large volume production due to its compatibility with the complementary metal-oxide semiconductor (CMOS) process. However, the high index-contrast between silicon and the top cladding (SiO2 or air) of the SOI waveguides leads to considerable modal birefringence. Consequently, SOI based PICs are in general highly polarization-sensitive, making polarization management a necessity. In this thesis, two polarization rotator (PR) designs on the 220 nm SOI platform are demonstrated through numerical simulations and experiments. The demonstrated PR designs are based on asymmetrical periodic loaded waveguide structures. The demonstrated designs feature compact device footprint and can be fabricated by CMOS compactable process. Both designs have shown promising performance over the C-band wavelengths by simulations. However, the fabrication requirements are stringent for these two designs, thus the performance of the fabricated devices are limited by the current fabrication technology.