A Compact Polarization Beam Splitter Based on a Multimode Photonic Crystal Waveguide with an Internal Photonic Crystal Section

We present the design and simulation of an ultra-compact polarization beam splitter (PBS) by combining a photonic crystal (PhC) multimode waveguide and an internal PhC section. The PhC multimode waveguide is designed to collect the powers reflected by or transmitted through the internal PhC structure which serves as a polarization sensitive scatterer. Plane wave expansion (PWE) method is used to calculate the band structure and the finite-difference timedomain (FDTD) method is employed to obtain the spectrum response. The simulation results show that the present design can give an ultracompact PBS with high extinction ratio over a broad bandwidth.