Compact silicon TE-pass polarizer using adiabatically-bent fully-etched waveguides

A high-performance integrated silicon TE-pass polarizer is proposed and demonstrated. The polarizer uses a series of adiabatic waveguide bends that yield high extinction ratio for the TM polarization and low insertion loss for the TE polarization, and does not require special materials or complex fabrication steps. The polarizer, implemented on a silicon-on-insulator platform with a 220 nm silicon thickness, is measured to have insertion loss ≤ 0.37 dB (average 0.12 dB) and extinction ratio ≥ 27.6 dB (average 36.0 dB) over a 1.5 μm to 1.6 μm wavelength range, with a footprint of 63 μm × 9.5 μm. The trade-off between the footprint of the polarizer and its performance is established. While the analysis was done for a silicon-on-insulator platform, the concept is applicable to other waveguide geometries and integrated photonic platforms.