Ultrabroadband polarization rotator based on 45 deg W-slot dual-stair waveguide covering S plus C plus L plus U bands

An ultrawideband polarization rotator (PR) with low insertion loss (IL) based on silicon on insulator (SOI) platform is proposed. The input TM0/TE0-polarized modes can be rotated 90 deg simultaneous using a 45-deg W-slot dual-stair waveguide with varied width. Simulation results show that with a PR in length of 4.3 mu m, the IL is below 0.4 (0.42) dB and polarization extinction ratio (PER) is over 17 (16) dB for TE0-to-TM0 (TM0-to-TE0) mode conversion within bandwidth of 300 nm (from 1400 to1700 nm), which covers optical fiber communication S-, C-, L-, and U-bands. In addition, the fabrication tolerance is analyzed numerically. The proposed PR has excellent performance with compact footprint and will find potential application in large-scale high-performance PICs. (C) 2021 Society of Photo-Optical Instrumentation Engineers (SPIE)

Automated summary

The proposed ultrawideband polarization rotator on SOI platform demonstrates low insertion loss and high performance for polarization mode conversion, making it suitable for various optical fiber communication bands.