利用描述光纤放大器非线性折射率的公式,通过数值模拟的方法模拟了输入信号功率、抽运功率、信号波长以及增益效应和克尔效应等变量对掺钕光纤放大器非线性折射率的影响,结果表明无论是增加抽运光功率或信号光功率,当信号光的波长小于1064 nm时,掺钕光纤放大器的非线性折射率的数值在此波段附近所对应的值为正值,大于此值所对应的值为负值;抽运功率较小时增益效应对非线性折射率的影响较大,而抽运功率较大时克尔效应对非线性折射率的影响较大,这主要是增益饱和所导致的结果;当信号光频率一定时,随抽运功率的增加非线性折射率逐渐增加并达到饱和。

This paper gives a numerical research on the Nd-doped fiber amplifier nonlinear refractive index and phase changing with the input signal power, pump power, signal wavelength, gain effect and Kerr effect. The results show that when the signal or pump power increases, the nonlinear refractive index is positive for the signal wavelength being smaller than 1064 nm, and negative for the signal wavelength being bigger than 1064 nm. When the signal wavelength hold a certain value, the nonlinear refractive index increases with the pump power. When the pump is low, the gain effect have more influence on the change of nonlinear refractive index, and when the pump is high, the Kerr effect have more influence on the change of nonlinear refractive index, which caused mainly by gain saturation.