摘要
基于改进的空间光谱分辨成像法,探究熔接参数对不同类型光纤熔接点处模式耦合特性的影响,通过调整步进来改变放电参数,量化分析影响熔接点处模式耦合的关键指标。结果表明,小包层光纤熔接的模式耦合特性受放电持续时间的影响较大,高阶模激发含量与放电时间呈正相关;当包层尺寸不同的光纤熔接时,角向模式耦合主要受到细光纤切割角度影响,而径向模式耦合受熔接参数影响较小;由于放电中心偏移和电极放电特性波动,包层尺寸不同的光纤熔接时热效应对熔点模式特性的影响具有随机性,包层尺寸差异越大熔接一致性越差;相反,大包层同尺寸光纤熔接对放电参数的变化不敏感,模式耦合特性在较大的放电参数范围内保持稳定。
Objective Fiber splicing is a fundamental procedure in constructing allfiber communication networks or fiber laser systems.Mode coupling occurring at the splicing point is a major cause of modal crosstalk and beam degradation in fewmode fibers.The performance of the splicing equipment significantly influences the mode coupling characteristics.Testing mode degradation at the splicing point is essential for determining optimal splicing parameters.In fewmode fiber splicing,mode coupling occurs simultaneously at the launching end and the splicing point,leading to a reciprocal mode coupling regime along the cascade fiber path.The traditional timedomain measurement methods require long transmission paths to accumulate total time delays of different modes and cannot distinguish or determine highorder modes,making it challenging to analyze mode coupling at the splicing point.Currently,fiber laser systems frequently involve fewmode fiber splicing,making it difficult to differentiate multiplemode coupling events.To achieve a comprehensive understanding of mode properties at the splicing point,it is necessary to explore a modified method that can decouple and quantify mode coupling characteristics in fewmode fiber architectures.Methods We propose a modified spatially and spectrally(M-S^(2))resolving method that accounts for the reciprocal mode coupling regime in fewmode fiber splicing.This method allows for the separation and decoupling of different origins of mode coupling at the splicing point,facilitating quantifiable analysis of specific highorder modes.Numerical simulations are conducted with different mode coupling events and modal weights are conducted to evaluate the method’s effectiveness,showing strong potential for analyzing mode coupling characteristics at the splicing point.An experimental setup,as shown in Fig.4,is constructed to investigate splicing.A tunable source,operating between 1070 nm and 1090 nm,injects singlemode laser beams into the fibers under test with a 0.05 nm wavelength interval.Each wavelen
作者
陈潇
黄善旻
黄良金
闫志平
潘志勇
姜宗福
周朴
Chen Xiao;Huang Shanmin;Huang Liangjin;Yan Zhiping;Pan Zhiyong;Jiang Zongfu;Zhou Pu(College of Advanced Interdisciplinary Studies,National University of Defense Technology,Changsha 410073,Hunan,China;Nanhu Laser Laboratory,National University of Defense Technology,Changsha 410073,Hunan,China;Hunan Provincial Key Laboratory of High Energy Laser Technology,National University of Defense Technology,Changsha 410073,Hunan,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2024年第20期173-186,共14页
Acta Optica Sinica
基金
国家重点研发计划(2022YFB3606000)。
关键词
激光光学
少模光纤
光纤熔接
模式耦合
电弧放电
光纤激光
laser optics
fewmode fiber
fiber fusion splicing
mode coupling
arc discharge
fiber laser
