为了能够更好地研究反折射率增益导引光纤的工作特性及掺镱反折射率增益导引光纤放大器模型,分析其对信号光的放大特性,利用信号光饱和参量S方法,求解速率方程,针对100μm芯径特征尺寸,进行了理论分析及仿真计算。结果表明,在特定的掺杂离子浓度和抽运功率下,得到信号光增益与光纤长度的相互关系,并得到最佳光纤长度、掺杂离子浓度和抽运功率的数值曲线,与普通的光纤放大器相比,其放大特性有很大的提高。

With the purpose of further discussion on the property of amplification of gain-guided and index-antiguided Yb-doped fiber amplifiers,with a negative refractive index step from the cladding to the core,the gain characteristics of a Yb³⁺-doped fiber in a diameter of 100μm were obtained after solving propagation rate equations by means of signal saturation S method.The relationship between the signal gain and the fiber length was obtained under a certain condition of doping concentration and pumping power and the curve was drawn.Comparing with a common fiber amplifier,the amplification property of this gain-guided and index-antiguided fiber was highly improved.