Affiliation:
1. School of Optoelectronic Engineering, Xidian University, Xi’an 710071, China
2. Science and Technology on Electromechanical Dynamic Control Laboratory, Xi’an 710065, China
Abstract
The key components of a polarization-independent electro-optic (EO) interferometer, including the beam splitter, mode converter, and directional coupler, are designed based on a lithium niobate (LN) platform on an integrated insulator to ensure high extinction ratios. By elaborately designing the geometric structure of the multimode interference (MMI) coupler, beam splitting of equal proportions and directional coupling of higher-order modes are realized. The most prominent characteristic of the proposed interferometer is polarization insensitivity, which is realized by converting TM polarization into TE polarization using a mode converter, providing conditions for the study of light with different polarizations. At 1550 nm, the visibility of the interferometer is 97.59% and 98.16% for TE and TM, respectively, demonstrating the high performance of the proposed LN polarization-independent interferometer.
Funder
National Natural Science Foundation of China
2021 Open Project Fund of Science and Technology on Electromechanical Dynamic Control Laboratory, China
the Open Research Fund of State Key Laboratory of Pulsed Power Laser Technology
Natural Science Foundation of Shaanxi Province, China