一种双零色散光子晶体光纤的高非线性研究

Research on High Nonlinearity of Photonic Crystal Fiber with Two Zero Dispersion Wavelengths

运用多极法,通过优化孔节距和包层空气孔半径设计了一种具有双零色散波长的高非线性光子晶体光纤,利用分步傅里叶方法数值模拟了超短脉冲在其中传输的情况,发现经过传输,两个零色散波长之间的主要能量被转换至位于正常色散区的两个边带峰处。泵浦的转化率很高,以至于多于99%的光能都被转移至两边带峰,且两边带峰很平坦,它们对波长波动,但对脉冲能量和泵浦脉冲的啁啾不敏感,这就产生了高稳定性的谱带。

By applying the method of multi-pole, a kind of photonic crystal fiber with two zero dispersion wavelengths is investigated based on the optimization of the pitch and the diameter of cladding hole. The slip-step Fourier method is used to numerically simulate the transmission of ultra-short pulses in this high nonlinear fiber. Simulation results show that, the majority energy between the two zero dispersion wavelengths is transformed into the two spectral lobes. The efficiency of pumping is so high that more than 99 % input energy can be transferred into the two flat spectral lobes which fluctuate with wavelength and are insensitive to pulse energy and chirp of pump pulse, thus resulting in the high stability of spectra.