椭圆芯有源光纤中模式的增益特性  

Modal Gain Characteristics in Active Fibers with Elliptical Core

作　　者：王齐全 武保剑[1] 江歆睿 Wang Qiquan;Wu Baojian;Jiang Xinrui(Key Laboratory of Optical Fiber Sensing and Communications,Ministry of Education,University of Electronic Science and Technology of China,Chengdu 611731,Sichuan,China)

机构地区：[1]电子科技大学光纤传感与通信教育部重点实验室,四川成都611731

出　　处：《光学学报》2022年第21期123-129,共7页Acta Optica Sinica

基　　金：国家自然科学基金(62171078);国家重点研发计划(2018YFB1801003)。

摘　　要：为实现少模掺铒光纤放大器(FMEDFA)的线偏振(LP)模态控制,采用多物理场仿真软件研究了椭圆芯光纤中的模场分布及其有效折射率随椭圆参数(纤芯的长短轴之比)的演化。当椭圆参数大于1.050时,TM_(01)和HE_(21o)、TE_(01)和HE_(21e)分别演化为LP_(11)奇模和偶模,奇偶模的有效折射率差大于10^(-4),模式串扰可以忽略。用LP模的叠加形式近似表达椭圆芯光纤中的模场,比较了椭圆芯有源光纤中LP近似模场与精确模场的增益计算误差。当椭圆参数小于1.250时,采用LP近似模场计算的三模增益误差小于0.5 dB。研究结果表明,采用LP近似模场分析方法可大大降低椭圆芯FMEDFA的设计复杂性。In order to control the linear polarization(LP)mode in fewmode erbiumdoped fiber amplifiers(FMEDFAs),the dependence of mode field distribution and effective refractive index in optical fibers with elliptical cores on the elliptical parameter(the ratio of the major to minor axis length of the elliptical core)is investigated by multiphysics field simulation software.When the elliptical parameter is more than 1.050,TM_(01) and HE_(21o),as well as TE_(01) and HE_(21e) can be expressed by LP_(11) odd and even modes which have an effective refractive index difference of larger than 10−4,with negligible mode crosstalk.This paper approximately constructs the mode field in an optical fiber with an elliptical core through the superposition of the LP modes,and compares the gain errors calculated by the approximate LP mode field and the precise mode field in the active fiber with an elliptical core.When the elliptical parameter is less than 1.250,the threemode gain error calculated by the approximate LP mode field is smaller than 0.5 dB.The results show that the approximate LP mode field can greatly reduce the design complexity of FMEDFAs with elliptical cores during analysis.

关 键 词：光纤光学 掺铒光纤放大器 椭圆纤芯 模态控制 

分 类 号：O436[机械工程—光学工程]