双注入双芯非线性光纤耦合器的开关特性分析

Switching characteristics of two-core nonlinear fiber optical couplers with two simultaneous pulses input

利用Lagrange变分法,导出了双芯非线性光纤耦合器中宽度可变的双曲正割型类孤子脉冲传播过程中参量满足的微分方程组,通过势函数图像,讨论了双芯同时注入孤子脉冲条件下耦合器的开关性质.结果表明,当输入的两基孤子脉冲一强一弱时,初始脉冲的相位差对耦合器开关特性影响显著,在初相位差取±π/2时开关效应对初相位差变化最敏感,提高注入孤子能量或增大耦合长度都有助于提高开关的相敏特性.

The Lagrangian formulation of variational principle was applied to deriving a set of differential equations.The soliton parameters of hyperbolic secant type soliton-like pulses with variable width propagating in two-core nonlinear optical fibers satisfied the equations.In the case of two soliton-like pulses input,switching properties of the coupler were analyzed with the potential function picture.The result shows that the initial phase difference of the solitons has a great influence on switching effect when one input pulse is strong whereas the other is weak.The switching effect is very sensitive to the variation of the initial phase difference when initial phase difference is ±π/2.Increasing both total input energy and coupling length can enhance the above-mentioned phase sensitivity.