High-Q lithium niobate microring resonators using lift-off metallic masks [Invited]

作     者：Ke Zhang Zhaoxi Chen Hanke Feng Wing-Han Wong Edwin Yue-Bun Pun Cheng Wang 张珂;陈朝夕;冯寒珂;黄咏娴;潘裕斌;王骋

作者机构：Department of Electrical EngineeringCity University of Hong KongKowloonHong KongChina State Key Laboratory of Terahertz and Millimeter WavesCity University of Hong KongKowloonHong KongChina 

出 版 物：《Chinese Optics Letters》 (中国光学快报（英文版）)

年 卷 期：2021年第19卷第6期

页      面：44-49页

核心收录：

学科分类：080904[工学-电磁场与微波技术] 081702[工学-化学工艺] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0817[工学-化学工程与技术] 

基　　金：supported by the National Natural Science Foundation of China(No.61922092) Research Grants Council,University Grants Committee(No.City U 21208219) City University of Hong Kong(Nos.9667182,9610402,and 9610455) 

主　　题：lithium niobate optical resonators microstructure fabrication 

摘      要：High-Q lithium niobate(LN) optical micro-resonators are an excellent platform for future applications in optical communications, nonlinear optics, and quantum optics. To date, high-Q factors are typically achieved in LN using either dielectric masks or femtosecond laser ablation, while the more standard and commonly available lift-off metallic masks are often believed to lead to rough sidewalls and lowered Q factors. Here, we show that LN microring resonators with strong light confinement and intrinsic Q factors over 1 million can be fabricated using optimized lift-off metallic masks and dry etching processes, corresponding to a waveguide propagation loss of ~0.3 d B=cm. The entire process is fully compatible with wafer-scale production and could be transferred to other photonic materials.