Silicon-on-insulator polarization controller with relaxed fabrication tolerances

Polarization control is essential in applications ranging from optical communications to interferometric sensors. The implementation of integrated polarization controllers is challenging as they require polarization rotating waveguides with stringent fabrication tolerances. Here, we present a fully integrated polarization controller scheme that significantly relaxes the requirements on the rotating waveguides, alleviating fabrication tolerances. We analytically establish a technology-independent, easily measurable tolerance condition for the rotating waveguides. Polarization control in the presence of waveguide width errors of ~25 % is shown through full vectorial simulation.