We demonstrate a polarization splitter rotator (PSR) based on multimode waveguide grating (MWG) on a silicon-on-insulator (SOI) platform. Bloch mode hybridization in mini-stopband is exploited to achieve high polarization conversion efficiency. The fabricated device yields a high extinction ratio of > 53 dB and > 31 dB, low crosstalk of < −26.4 dB and < −40 dB for the injected TE0 and TM0 mode, with average insertion loss of 1.2 dB and 1.5 dB in the wavelength regime 1552 nm–1562 nm. Such a device shows great design flexibility and an easy fabrication process, serving as a good candidate in integrated polarization diversity circuits, especially for applications requiring spectra manipulation. Additionally, the polarization conversion approach provides opportunities to develop novel polarization management devices.
High extinction ratio polarization selective TE/TM Bragg gratings filters on silicon-on-insulator