Pompili R, Anania M P, Bisesto F, Botton M, Chiadroni E, Cianchi A, Curcio A, Ferrario M, Galletti M, Henis Z, Petrarca M, Schleifer E, Zigler A
Laboratori Nazionali di Frascati, 00044, Frascati, Italy.
Racah Institute of Physics, Hebrew University, 91904, Jerusalem, Israel.
Sci Rep. 2018 Feb 19;8(1):3243. doi: 10.1038/s41598-018-21711-4.
The interaction of high-power ultra-short lasers with materials offers fascinating wealth of transient phenomena which are in the core of novel scientific research. Deciphering its evolution is a complicated task that strongly depends on the details of the early phase of the interaction, which acts as complex initial conditions. The entire process, moreover, is difficult to probe since it develops close to target on the sub-picosecond timescale and ends after some picoseconds. Here we present experimental results related to the fields and charges generated by the interaction of an ultra-short high-intensity laser with metallic targets. The temporal evolution of the interaction is probed with a novel femtosecond resolution diagnostics that enables the differentiation of the contribution by the high-energy forerunner electrons and the radiated electromagnetic pulses generated by the currents of the remaining charges on the target surface. Our results provide a snapshot of huge pulses, up to 0.6 teravolt per meter, emitted with multi-megaelectronvolt electron bunches with sub-picosecond duration and are able to explore the processes involved in laser-matter interactions at the femtosecond timescale.
高功率超短激光与材料的相互作用展现出了一系列引人入胜的瞬态现象，这些现象是新型科学研究的核心。解读其演化过程是一项复杂的任务，这在很大程度上取决于相互作用早期阶段的细节，而这一早期阶段起着复杂初始条件的作用。此外，整个过程很难探测，因为它在亚皮秒时间尺度上靠近靶材发生，并在几皮秒后结束。在此，我们展示了与超短高强度激光与金属靶材相互作用所产生的场和电荷相关的实验结果。利用一种新型的飞秒分辨率诊断方法来探测相互作用的时间演化，这种方法能够区分高能先驱电子的贡献以及靶材表面剩余电荷电流所产生的辐射电磁脉冲的贡献。我们的结果提供了一幅快照，展示了高达每米0.6太伏的巨大脉冲，这些脉冲由持续时间为亚皮秒的多兆电子伏特电子束发射产生，并且能够在飞秒时间尺度上探索激光与物质相互作用所涉及的过程。
