Generation of intense isolated attosecond pulses for attosecond nonlinear opitcs

我们已经产生了高能量的孤立阿秒脉冲，其强度足以在原子和分子中诱发非线性现象。基于氮分子双光子双电离的自相关测量直接表征了脉冲宽度。通过精心设计的生成配置，我们获得了孤立的阿秒脉冲的能量高达1.3微焦耳/脉冲，从而显示其能量增强从100到1000倍，与以前的报告相比，到目前为止。从由自相关方法确定的500-as脉冲持续时间，该隔离的阿秒脉冲的峰值功率被评估为2.6 GW。该方法的提出为阿秒科学前沿的研究铺平了道路，必将给超快现象和非线性光学的研究带来巨大的飞跃。

We have generated high energy isolated attosecond pulses, which are intense enough to induce the nonlinear phenomena in atoms and molecules. The pulse width was direct characterized by autocorrelation measurement based on two-photon double ionization in nitrogen molecules. By carefully designing the generation configurations, we obtained isolated attosecond pulses with energy up to 1.3 micro Joule/pulse, thus showing its energy enhancement from 100- to 1000-fold compared with the previous report so far. From a 500-as pulse duration determined by the autocorrelation method, the peak power of this isolated attosecond pulse was evaluated to be 2.6 GW. The presented method paves the way for the intense attosecond science frontier, which will certainly bring a great leap forward in research on ultrafast phenomena and nonlinear optics.