单模光纤中超短脉冲的前向四波混频

给出了一组在单模光纤中超短脉冲前向四波混频的耦合波方程。利用这组方程所作的数值研究表明：在低转换和脉冲的走离远小于脉冲宽度的条件下，越短脉冲前向四波混凝的转换效率对相位失配的关系与连续波四波混频情况基本相同，不存在使增益为零的Δｋ（ｋ为不考虑非线性折射率时模的波数）的取值区间，蛤峰值条件应该是Δｋ＝０（ｋ为计及非线性折射率时模的波数），而不是Δｋ＝０；窄脉冲的转换效率略低且峰值位置与Δｋ＝０稍有偏

Forward Four-Wave Mixing of Ultra-Short Pulses in Single Mode Optical Fibers

The couple-wave equations of forward four-wave mixing (FFWM) of ultra-short pulses in single mode optical fibers are given. Numerical investigations using the equations show that, when the walk-off of the pulses is much less than the width of the pulses and the conversion efficiency is lower, the dependence of the FFWM conversion effeciency on the phase mismaching for ultra-short pulses is samilar as in FFWM of continuous waves, there are not any amount ranges of Δk (where k is the mode propagation number un-involving the nonlinear refractive index) wich make the gain equal to zero, and the peak conversion condition should be Δκ=0 (where κ is the mode propagation number which involves the nonlinear refractive index) but not Δk=0. The conversion efficiency is smaller slightly and the peak gain conditions bias a little from Δκ=0 for narrower pulses. Realization of Δk=0 can avoid the broadening and distortion of the pulses to the greatest extent.