Silicon photonic devices for signal processing in wavelength, polarization and mode

We experimentally demonstrate optical filtering, polarization splitting and rotating, and mode (de)multiplexing and switching in silicon devices.

We firstly demonstrate silicon photonic filters based on Sagnac loop reflectors, including a wavelength and bandwidth-tunable comb filter, and two compact interleavers in the Michaelson interferometer and interfering loop configurations with compact footprints.

We then discuss a high extinction-ratio (30 dB) silicon polarization beam splitter (PBS) based on a grating-assisted contra-directional coupler (GACC), and an ultra-compact silicon polarization splitter and rotator (PSR) with a short coupling length of 8.77 micron.

We further talk about optical switching in wavelength, mode, and polarization. We demonstrate a 2x2 nanobeam thermal-optic switch with ultra-small mode volumes, a high tuning efficiency of 1.23 nm/mW and an ultra-low switching power of 0.16 mW. We then propose a mode- and polarization-selective switch (MPSS) architecture for next generation high capacity switching systems, and demonstrate 1x2 and 2x2 on-chip MPSS switches.