Polarization management for silicon photonic integrated circuits

TLDR

Polarization management is critical for silicon photonic integrated circuits because geometrical anisotropy, fabrication inaccuracies, and polarization‑dependent dispersion and loss create significant differences between TE and TM modes, especially in high‑index‑contrast SOI nanophotonic waveguides. The authors review their work on polarization management for silicon PICs using polarization‑independence and polarization‑diversity methods. They discuss polarization issues and solutions in SOI nanowire and ridge waveguide PICs.

Abstract

Abstract Polarization management is very important for photonic integrated circuits (PICs) and their applications. Due to geometrical anisotropy and fabrication inaccuracies, the characteristics of the guided transverse‐electrical (TE) and transverse‐magnetic (TM) modes are generally different. Polarization‐dependent dispersion and polarization‐dependent loss are such manifestations in PICs. These issues become more severe in high index contrast structures such as nanophotonic waveguides made of silicon‐on‐insulator (SOI), which has been regarded as a good platform for optical interconnects because of the compatibility with CMOS processing. Recently, polarization division multiplexing (PDM) with coherent detection using silicon photonics has also attracted much attention. This trend further highlights the importance of polarization management in silicon PICs. The authors review their work on polarization management for silicon PICs using the polarization independence and polarization diversity methods. Polarization issues and solutions in PICs made of SOI nanowires and ridge waveguides are discussed.