中心凹陷型少模掺铒光纤中的模场调控与增益均衡  

Mode Field Modulation and Gain Equalization with Central Depressed Few-Mode Erbium-Doped Fiber

作　　者：徐文轩 裴丽[1,2] 王建帅[1,2] 李祉祺 赵琦 郑晶晶[1,2] 李晶[1,2] 宁提纲[1,2] 钟力 Xu Wenxuan;Pei Li;Wang Jianshuai;Li Zhiqi;Zhao Qi;Zheng Jingjing;Li Jing;Ning Tigang;Zhong Li(Key Laboratory of All Optical Network and Advanced Telecommunication Network,Ministry of Education,Beijing Jiaotong University,Beijing 100044,China;Institute of Lightwave Technology,Beijing Jiaotong University,Beijing 100044,China;State Key Laboratory of Optical Fiber and Cable Manufacture Technology,Yangtze Optical Fiber and Cable Joint Stock Limited Company,Wuhan 430073,Hubei,China)

机构地区：[1]北京交通大学全光网络与现代通信网教育部重点实验室,北京100044 [2]北京交通大学光波技术研究所,北京100044 [3]长飞光纤光缆股份有限公司光纤光缆制备技术国家重点实验室,湖北武汉430073

出　　处：《光学学报》2022年第21期130-139,共10页Acta Optica Sinica

基　　金：国家重点研发计划(2018YFB1801003)。

摘　　要：中心折射率凹陷型少模掺铒光纤(FMEDF)可以改变传输模式的数量和截止顺序,在模场调控和增益均衡方面具有良好的性能。利用等效折射率理论描述光纤模式截止特性,研究了由传统阶跃折射率光纤向环芯光纤转变过程中的模式变化。结果表明,当中心凹陷大于0.012时,光纤仅支持LPn1模式传输,且使得LP01模场能量向远离中心区域方向偏移。此外,当光纤用于信号放大领域中,且折射率凹陷数值大小与掺杂区域半径之间符合相应的线性关系时,模式增益差可保持在2 dB以下。采用自制的中心凹陷型FMEDF对LPn1模式的增益特性进行了实验测试。实验结果表明,各信号模式增益均大于18 dB,模式增益差为1.3 dB。A central refractive index depressed fewmode erbiumdoped fiber(FMEDF)can change the number and cutoff order of transmission modes,and has an excellent performance in terms of mode field modulation and gain equalization.In this paper,the equivalent refractive index theory is employed to describe the cutoff characteristics of optical fiber modes,and the changes of modes during the transition from the traditional stepindex fibers to ringcore fibers are studied.The results show that when the central depression is larger than 0.012,the optical fiber only supports LPn1 mode transmission and makes the field energy of LP01 mode shift away from the central areas.Additionally,when the optical fiber is used in signal amplification areas,and there is a corresponding linear relationship between the refractive index depression and the radius of the doped region,the differential modal gain can be kept below 2 dB.A homemade central depressed FMEDF is used to test the gain characteristics of LPn1 mode.The experimental results show that the gain of all signal modes is higher than 18 dB,and the differential modal gain is 1.3 dB.

关 键 词：光通信 光纤通信 少模掺铒光纤 中心凹陷 模式增益均衡 环芯光纤 

分 类 号：TN929.11[电子电信—通信与信息系统]