单模双折射色散缓变光纤中拉曼散射与参量放大

Raman Scattering and Parametric Amplification in Single-mode Birefringence Dispersion-decreasing Fiber

根据斯托克斯波和反斯托克斯波所满足的耦合微分方程,考虑泵浦波是线偏振光,其偏振方向沿x轴,推导出了同偏振方向受激拉曼散射和参量放大同时作用下,斯托克斯波和反斯托克斯波的增益系数。研究了色散缓变光纤中增益随失配系数Δk2以及归一化距离z/L的变化关系。结果表明,当非线性系数γ=0时,增益随Δk2的变化情况在正常和反常色散区是完全对称的;而当非线性系数γ≠0时,在反常色散区增益会出现峰值,随后增益随Δk2和z/L的增加而逐渐减小。讨论了反斯托克斯波与斯托克斯波Eax/Esx的比值随失配系数Δk2的增加而快速衰减的变化特性。

According to the coupling differential equations of the Stokes and anti-Stokes,the pump wave is linearly polarized and aligned with the x-axis direction.The gain coefficients have been reduced for the Stokes and anti-Stokes which simultaneously act of stimulated Raman scattering and parametric amplification in the same x polarization.The gain changes with mismatch Δk2 and normalized distance z/L in dispersion-decreasing fiber are obtained.It is observed that gain coefficient changes with the mismatch Δk2 is symmetrical when non-linear coefficient γ=0,in normal dispersion regime and anomalous dispersion regime.The gain will arise a peak and then with the Δk2 and z/L increases gradually reduce in the anomalous dispersion regime when non-linear coefficient γ≠ 0.At the same time the feature about energy ratio of Stokes and anti-Stokes Eax/Esx reduced rapidly with increase of mismatch Δk2.