AI 中文总结
该研究通过调控激光脉冲的持续时间与强度，控制光驱动绝缘体的亚周期多带电子动力学，实现高次谐波产生的路径选择性，将高次谐波截止能量拓展至25-50 eV，为高能极紫外光源设计提供了新方法。
AI 中文摘要
我们通过联合调控激光脉冲持续时间（5-29 fs）和强度（0.8-74 TW/cm²），实现了对极紫外高次谐波产生的路径选择性控制。中等强度（约6 TW/cm²）的多周期脉冲会促使载流子在连续光学周期内发生累积转移，逐步占据更高的导带；相比之下，少周期、高强度（约22 TW/cm²）的脉冲则会驱动亚周期多带动力学，在退相干抑制相干发射前达到25-50 eV的光子能量。这些结果表明，脉冲持续时间和强度是调控高次谐波发射的关键旋钮，为设计基于能带结构的更高能量极紫外光源开辟了途径。
英文摘要
We demonstrate pathway-selective control of extreme-ultraviolet high-harmonic generation by jointly tuning laser pulse duration ($5$ - $29$ fs) and intensity ($0.8$ - $74$ TW/cm$^2$). Many-cycle pulses at moderate intensities, $\sim 6$ TW/cm$^2$, promote cumulative carrier transfer over successive optical cycles, progressively accessing higher conduction bands. In contrast, few-cycle, high-intensity, $\sim 22$ TW/cm$^2$, pulses drive subcycle multiband dynamics that reach $25$ - $50$ eV photon energies before decoherence can suppress coherent emission. These results reveal pulse duration and intensity as decisive control knobs for high-harmonic emission, opening a route to band-structure-guided pulse design for higher energy extreme-ultraviolet light sources.
