啁啾指数脉冲的非线性传输研究

数值研究了初始线性啁啾指数光脉冲在单模光纤反常色散区的非线性传输特性,并将这种特性与双曲正割脉冲的相关特性作了比较.脉冲振幅A=1时,负啁啾对脉冲时域宽度展宽的影响比正啁啾大;指数脉冲受啁啾影响比双曲正割脉冲更敏感.A＞1.2时,脉宽在演化过程中呈周期性衰减振荡,振荡周期和振幅随啁啾|C|(|C|≤2)的增大而增大,最后能演化成光孤子.脉冲演化成光孤子所需的最小振幅A比啁啾双曲正割脉冲的大.

Research on nonlinear propagation of chirped exponential pulses

The nonlinear propagation characteristics of exponential optical pulses with initial linear frequency chirps in an anomalous-dispersion single mode fiber are numerically studied and compared with those of hyperbolic secant pulses. The effect of the negative chirp on pulse broadening is greater than that of the positive chirp when pulse amplitude A=1 and the exponential pulse is more sensitive to the impact of the chirp than the hyperbolic secant pulse. When A＞1.2, the pulse width oscillates in a periodically damped manner with the propagating distance and the period and amplitude of the oscillation increase with the increase of chirp parameter |C| when |C|≤2. The exponential pulse finally evolves into an optical soliton and the minimal value A required for this evolution is larger than that of hyperbolic secant pulse.