一种高双折射光子晶体光纤中的脉冲俘获分析

数值模拟分析了一种新型高双折射光子晶体光纤中的脉冲俘获现象,以及泵浦脉冲入射条件对脉冲俘获效果的影响机理.结果表明：泵浦脉冲和信号脉冲处于零色散点附近,且分别处于光子晶体光纤的反常和正常色散区,其走离参量的数值小于10－12 s/m时,可以实现脉冲俘获|泵浦脉冲和信号脉冲的时域中心延迟对泵浦脉冲光谱红移量和信号脉冲光谱蓝移量影响很小,但时域中心延迟越大,信号脉冲的输出频谱越窄,俘获效果越差|提高泵浦脉冲峰值功率,可明显增大泵浦脉冲光谱红移量和信号脉冲光谱蓝移量,为实现不同波长范围的全光开关提供了条件|泵浦脉冲半宽度越大,泵浦脉冲频谱越宽,信号脉冲频谱越窄,俘获效果越不明显.

Analysis of Pulse Trapping Characteristic in Highly Birefringent Photonic Crystal Fiber

 A theoretical investigation of the pulse trapping in a highly birefringent photonic crystal fiber was presented.The strict coupled nonlinear Schrdinger equations were numerically solved using a split-step Fourier algorithm.Different incidence conditions were discussed when the two pulses were polarized along the same polarization axes.The pump pulse in abnormal dispersion regime traped the signal pulse in the normal dispersion regime,and the signal pulse shifted to shorter wavelength with the pump pulse of the longer wavelength in order to keep the same group velocity.Different initial temporal separation between the pump pulse and the signal pulse leaded to different effect in the pulse trapping.As the input peak power of the pump pulse was increased,the red-shift of pump pulse was considerably enhanced with the simultaneous further blue-shift if the trapped pulse to satisfy the condition of group velocity matching.Pulse trapping was inconspicuous as the full width at half maximum of the pump pulse was increased.In order to realize pulse trapping,the wavelengths of the pump and signal pulses should be near the zero dispersion point and the discrepancy between two group velocities should be small.