High quality integrated optical polarizers in LiNbO3

Ti: LiNbO3 integrated optical circuits are playing an increasingly important role in fiber optic sensor technology. To obtain acceptable performance in these systems, the power in the LiNbO3 circuit must be linearly polarized and confined to the extraordinary mode. In this work, the authors describe a proton-exchanged polarizer operating at 0.8-0.85 μm in x-cut LiNbO3 which provides 55-60 dB polarization extinction with very low (0.2 dB) excess loss. This represents a 15-20 dB improvement over the best integrated optical polarizer results reported to date in LiNbO3