Silicon nitride assisted tri-layer edge coupler on lithium niobate-on-insulator platform

• DOI: 10.1364/ol.492372
• Publication Date: 2023-05-25T14:00:07Z
• Authors: Zhiguo Yu; Yuxiang Yin; Xingrui Huang; Donghe Tu; Hang Yu; Huan Guan; Lei Jiang; Wei Yan; Zhiyong Li
• Keywords: Photons; Silicon Compounds; Oxides

Lithium niobate-on-insulator (LNOI) is a promising integration platform for various applications, such as optical communication, microwave photonics, and nonlinear optics. To make niobate (LN) photonic integrated circuits (PICs) more practical, low-loss fiber–chip coupling essential. In this Letter, we propose experimentally demonstrate silicon nitride (SiN) assisted tri-layer edge coupler on LNOI platform. The consists of bilayer LN taper an interlayer structure composed 80 nm-thick SiN waveguide strip waveguide. measured loss the TE mode 0.75 dB/facet at 1550 nm. Transition between ∼0.15 dB. addition, fabrication tolerance in high.