Lan Pengfei, Ruhmann Marc, He Lixin, Zhai Chunyang, Wang Feng, Zhu Xiaosong, Zhang Qingbin, Zhou Yueming, Li Min, Lein Manfred, Lu Peixiang
School of Physics and Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
Institute for Theoretical Physics and Centre for Quantum Engineering and Space-Time Research (QUEST), Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany.
Phys Rev Lett. 2017 Jul 21;119(3):033201. doi: 10.1103/PhysRevLett.119.033201.
We report attosecond-scale probing of the laser-induced dynamics in molecules. We apply the method of high-harmonic spectroscopy, where laser-driven recolliding electrons on various trajectories record the motion of their parent ion. Based on the transient phase-matching mechanism of high-order harmonic generation, short and long trajectories contributing to the same harmonic order are distinguishable in both the spatial and frequency domains, giving rise to a one-to-one map between time and photon energy for each trajectory. The short and long trajectories in H_{2} and D_{2} are used simultaneously to retrieve the nuclear dynamics on the attosecond and ångström scale. Compared to using only short trajectories, this extends the temporal range of the measurement to one optical cycle. The experiment is also applied to methane and ammonia molecules.
我们报告了对分子中激光诱导动力学的阿秒级探测。我们应用了高谐波光谱法，在该方法中，激光驱动的电子在各种轨迹上重新碰撞，记录其母离子的运动。基于高次谐波产生的瞬态相位匹配机制，对同一谐波阶数有贡献的短轨迹和长轨迹在空间和频域中都是可区分的，从而为每个轨迹在时间和光子能量之间产生一一映射。同时使用H₂和D₂中的短轨迹和长轨迹来获取阿秒和埃尺度上的核动力学。与仅使用短轨迹相比，这将测量的时间范围扩展到了一个光学周期。该实验也应用于甲烷和氨分子。
