摘要
铌酸锂薄膜因其优异光学性能及容易与结构紧凑的光波导等器件相集成等诸多优势,目前已经成为可调谐Fabry-Perot滤波器、电光调制器等器件领域向集成化和微小型化趋势发展的首选光学材料。由于光波导和光纤的尺寸差异而引起了严重的模场失配使得光纤与光波导耦合时存在着较大的插入损耗问题。仿真分析了超高数值孔径光纤和脊形波导直接耦合时,其光场模式分布、折射率、耦合效率和耦合损耗等关键性能的相互影响。结果表明当刻蚀深度和宽度分别为300 nm和0.8μm时,铌酸锂脊型波导与单模光纤(UHNA7)的耦合效率可达33.8%,而耦合损耗为4.71 dB。仿真比较了上包层材料替换为二氧化硅和氮化硅材料时,脊型波导和单模光纤的耦合效率显著增加到63.4%而耦合损耗被降低到1.98 dB。
Lithium niobate thin film has become the preferred optical material in the field of tunable Fabry-Perot filter,electro-optic modulator and other devices towards integration and miniaturization because of its excellent optical properties and the advantages of easy integration with compact optical waveguides and other devices. However,due to the size difference between optical waveguide and optical fiber,there is a serious mode field mismatch,which leads to a large insertion loss when the optical fiber is coupled with optical waveguide. In this paper,as an ultra-high numerical aperture(UHNA)fiber is directly coupled with ridge waveguide,optical properties such as light field mode distribution,coupling efficiency and loss are analyzed by simulation. The results show that as the etching depth and width are 300 nm and 0.8 μm,respectively,the coupling efficiency between the LiNbO3ridge waveguide and the single-mode fiber(UHNA7)can reach33.8% and the coupling loss is 4.71 d B. The simulation also compares that when the upper cladding material is replaced with silicon dioxide and silicon nitride materials,the coupling efficiency value of the ridge waveguide and single-mode fiber is significantly increased to 63.4% and the coupling loss is reduced to 1.98 dB.
作者
王珂珂
丹丽智
沈志强
靳辰飞
张思琦
WANG Ke-ke;DAN Li-zhi;SHEN Zhi-qiang;JIN Chen-fei;ZHANG Si-qi(School of Physics,Harbin Institute of Technology,Harbin 150001,China)
出处
《光学与光电技术》
2022年第5期70-76,共7页
Optics & Optoelectronic Technology
