TE/TM-pass polarizers based on lateral leakage in a thin film lithium niobate–silicon nitride hybrid platform
Yang Liu, Xingrui Huang, Zezheng Li, Yingxin Kuang, Huan Guan, Qingquan Wei, Zhongchao Fan, Zhiyong Li
Abstract
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 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>z</mml:mi> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo>/</mml:mo> </mml:mrow> <mml:mspace width="negativethinmathspace"/> <mml:mi>y</mml:mi> </mml:math> directions, respectively. Such TE/TM-pass polarizers can be integrated in the same wafer.