TE/TM-pass polarizers based on lateral leakage in a thin film lithium niobate–silicon nitride hybrid platform

TE/TM-pass polarizers based on the lithium niobate-silicon nitride hybrid platform are numerically proposed for the first time, to the best of our knowledge. By utilizing the lateral leakage of a shallowly etched rib waveguide, 1-mm-long TE/TM-pass polarizers with high extinction ratios of 28.72/24.03 dB are obtained. Because of the anisotropy of the lithium niobate, the lateral leakage of TE/TM polarization modes can occur along crystallographic z/y directions, respectively. Such TE/TM-pass polarizers can be integrated in the same wafer.