Integrated silicon metasurface polarization beam splitter on a standard SOI substrate

Polarization beam splitters are indispensable components in on-chip polarization-division-multiplexing systems. We propose a compact integrated polarization beam splitter based on a metasurface structure with a 300 nm periodic silicon column array with a variable duty cycle on a silicon-on-insulator substrate. Simulation results indicate a low insertion loss, high extinction ratio, and a 6x12 mu m2 footprint within the C+L band. The robustness of our device with respect to manufacturing tolerance and nonideal input light has also been confirmed. The proposed polarization beam splitter can be fabricated in a single lithography step with input/output waveguides, which will be advantageous for device fabrication.