LAUSR

Abstract This paper presents a compact dual-mode polarization beam splitter (PBS) based on silicon on insulator platform. The proposed PBS separates two lowest-order transverse magnetic (TM) modes from two lowest-order transverse electric (TE) ones by employing an optimized tapered directional coupler. To the best of our knowledge, this is the first PBS with the ability of separating two sets of modes with different polarizations, simultaneously. Such a component is an essential block in the hybrid mode/polarization-multiplexing systems. The three-dimensional finite-difference time-domain (FDTD) simulation results confirm that the designed PBS has a low loss of 1.6 dB and high extinction ratio of more than 10 dB over a broad wavelength range of 90 nm. Also, the presented PBS tolerates ± 15 nm change in the coupling gap, ± 30 nm waveguide width deflection, and more than ± 100 nm coupling length variation with an insertion loss lower than 1 dB and extinction ratio higher than 10 dB.