Abstract In this paper, the half-cycle harmonic generation process has been controlled by using the asymmetric inhomogeneous chirped pulse combined with the ultraviolet (UV) pulse. It is found that by properly optimizing the chirps and chirp delays of the fundamental two-color pulse, the optimal negative and positive half-cycle laser profiles for the harmonic cutoff extension can be obtained. Further, with the introduction of the negative and positive inhomogeneous effect, respectively, the harmonic cutoff from the negative and positive half-cycle laser profiles can be further improved. Next, with the assistance of the UV pulse, the harmonic intensity can be enhanced due to the UV resonance ionization. Moreover, the single and double UV photon resonance ionizations are much better for generating the higher harmonic intensity. As a result, the stronger and broader harmonic plateaus with the larger harmonic cutoff can be obtained, which can support the generation of the high-intensity ultrashort attosecond pulses with the pulse durations of sub-45 as.

中文翻译：

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控制产生强和超短阿秒单脉冲（SAPs）的半周期谐波发射过程

摘要 本文利用非对称非均匀啁啾脉冲结合紫外（UV）脉冲来控制半周谐波产生过程。发现通过适当优化基频双色脉冲的啁啾和啁啾延迟，可以获得用于谐波截止扩展的最佳负半周和正半周激光轮廓。此外，通过分别引入负和正非均匀效应，可以进一步改善负半周和正半周激光轮廓的谐波截止。接下来，在紫外脉冲的辅助下，由于紫外共振电离，可以增强谐波强度。此外，单紫外光子共振电离和双紫外光子共振电离对于产生高次谐波强度要好得多。因此，