基于双芯光子晶体光纤的耦合器设计方法  

Design Method of Coupler Based on Dual-Core Photonic Crystal Fibers

作　　者：王胜意 丁哲文 郑祥亮 赵春柳 Wang Shengyi;Ding Zhewen;Zheng Xiangliang;Zhao Chunliu(College of Optics and Electronic Technology,China Jiliang University,Hangzhou 310018,Zhejiang,China;The 41st Institute of China Electronics Technology Group Corporation,Qingdao 266555,Shandong,China)

机构地区：[1]中国计量大学光学与电子科技学院,浙江杭州310018 [2]中国电子科技集团公司第四十一研究所,山东青岛266555

出　　处：《光学学报》2024年第5期60-68,共9页Acta Optica Sinica

基　　金：国家自然科学基金(62305319);科工局技术基础项目(JSJL2022210C001);中国计量大学引进人才科研启动项目(01101-231047)。

摘　　要：采用光束传播法对双芯光子晶体光纤中光纤结构参数对纤芯间耦合效率的影响进行分析。首先,根据双芯耦合原理,使用最小二乘法对波导间的耦合系数等参数进行估计,明确孔间距、纤芯折射率差、中央空气孔直径比例、纤芯直径比例、空气孔直径比例和空气孔对称度等参数对双芯光子晶体光纤耦合比及耦合区长度的调节作用,提出一种基于双芯光子晶体光纤的耦合器性能粗调与微调设计方法。然后,根据这一耦合器设计方法,提出一种非对称的双芯光子晶体光纤宽带定向耦合器。该耦合器在1.31~1.55μm区间实现了50%±5%的耦合比,带宽为240 nm,并具有3 mm的超短耦合长度。本研究成果可为光纤宽带定向耦合器的高效设计提供有意义的参考。Objective Optical fiber directional coupler can realize beam coupling and splitting,which is one of the most important passive devices in the optical fiber communication system after the optical connector.In recent years,with the wide application of various high-capacity wavelength division multiplexing(WDM)communication networks,the bandwidth characteristics of optical fiber directional couplers are facing great challenges.As a practical product,the fabrication technology of optical fiber couplers based on the melt-drawing cone process is very mature and has the advantages of good directionality,high-temperature stability,and low cost.However,due to the strong dependence of the beam-splitting ratio on the operating wavelength,most of the current optical fiber directional couplers operate at specific wavelengths and have narrow bandwidths.The advent of photonic crystal fibers(PCFs)makes it possible to design fiber couplers with higher performance.Compared with traditional fiber couplers,PCF-based couplers have the advantages of low wavelength dependence,short coupling length,and low insertion loss,and they have become a hot spot in related research fields.Among them,the dual-core PCF-based directional coupler has been reported in many experimental and theoretical studies.However,most researchers usually give the structure and parameters of the designed coupler directly and do not make a more detailed summary and generalization of the specific rules of parameter design.If the specific rules of PCF parameter design are summarized in detail,it can provide a meaningful reference for the efficient design of broadband optical fiber directional couplers.Methods In a dual-core fiber,each core region can be considered as an independent optical waveguide,and the optical field energy conducted within each core is affected by the other core and changes periodically with the length of the coupling region.According to the coupling theory,it can be seen that for two parallel lossless optical waveguides,the internal optical fiel

关 键 词：光纤光学 双芯光子晶体光纤 光束传播法 耦合效率 宽带耦合器 

分 类 号：TN253[电子电信—物理电子学]