We demonstrate experimentally a relatively simple yet powerful all-optical enhancement and control technique for high-harmonic-generation. This is achieved by using as a pump beam two different spatial optical modes interfering together to realize tunable periodic quasi-phase-matching of the interaction. With this technique we demonstrate on-the-fly quasi-phase-matching of harmonic orders 29 to 41 at ambient gas pressure levels of 50 and 100 Torr, where up to 100 fold enhancement of the emission is observed. The technique is scalable to different harmonic orders and ambient pressure conditions.

中文翻译：

---

使用结构化泵浦光束对高次谐波的产生进行飞行控制

我们通过实验证明了一种相对简单但功能强大的用于高谐波产生的全光学增强和控制技术。这是通过将两个不同的空间光学模式干涉在一起以实现交互作用的可调周期性准相位匹配来实现的。通过这种技术，我们证明了在50和100 Torr的环境气压水平下，谐波阶次为29到41的动态准相位匹配，在这种情况下，观察到的发射强度提高了100倍。该技术可扩展到不同的谐波次数和环境压力条件。