Large Fabrication Tolerance Transverse Electric-Pass Polarizer on Thin-Film Lithium Niobate Platform

Based on the different transmission losses of transverse electric (TE) and transverse magnetic (TM) modes of light passing through a bent waveguide, this study experimentally demonstrates a TE-pass polarizer with low loss and a high fabrication tolerance for the waveguide width. Fabricated on a thin-film lithium niobate platform using 350 nm i-line lithography, the polarizer exhibits an insertion loss of < 1 dB and a polarization extinction ratio of > 13 dB (18.5 dB on average) within the O-band. These characteristics can be maintained even with waveguide width variations between -200 and +200 nm.