The effect of nonlinear chirp combination on the enhancement of harmonic cutoff and harmonic intensity has been investigated by using a two-color chirped pulse. It is found that with the combination of 2-order chirp form, the strongest intensity enhancement of harmonic spectrum can be found. While, with the combination of 2-order and 3-order chirp forms, the largest cutoff extension of the harmonic spectrum can be obtained. Finally, by properly using the harmonic spectra driven by the above two kinds of combined pulses, the single attosecond pulses (SAPs) of 43 as and 33 as can be generated.

中文翻译：

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非线性啁啾组合对高次谐波频谱和阿秒脉冲改善的影响

利用双色啁啾脉冲研究了非线性啁啾组合对谐波截止和谐波强度增强的影响。发现结合二阶啁啾形式，可以发现谐波谱的最强强度增强。而通过2阶和3阶啁啾形式的组合，可以获得谐波频谱的最大截止扩展。最后，通过适当利用上述两种组合脉冲驱动的谐波谱，可以产生43 as和33 as的单阿秒脉冲(SAP)。