Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str. 1, D-85748 Garching, Germany. Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, 18221 Prague, Czech Republic.
Rep Prog Phys. 2017 May;80(5):054401. doi: 10.1088/1361-6633/aa574e. Epub 2017 Jan 6.
Recently two emerging areas of research, attosecond and nanoscale physics, have started to come together. Attosecond physics deals with phenomena occurring when ultrashort laser pulses, with duration on the femto- and sub-femtosecond time scales, interact with atoms, molecules or solids. The laser-induced electron dynamics occurs natively on a timescale down to a few hundred or even tens of attoseconds (1 attosecond = 1 as = 10 s), which is comparable with the optical field. For comparison, the revolution of an electron on a 1s orbital of a hydrogen atom is ∼152 as. On the other hand, the second branch involves the manipulation and engineering of mesoscopic systems, such as solids, metals and dielectrics, with nanometric precision. Although nano-engineering is a vast and well-established research field on its own, the merger with intense laser physics is relatively recent. In this report on progress we present a comprehensive experimental and theoretical overview of physics that takes place when short and intense laser pulses interact with nanosystems, such as metallic and dielectric nanostructures. In particular we elucidate how the spatially inhomogeneous laser induced fields at a nanometer scale modify the laser-driven electron dynamics. Consequently, this has important impact on pivotal processes such as above-threshold ionization and high-order harmonic generation. The deep understanding of the coupled dynamics between these spatially inhomogeneous fields and matter configures a promising way to new avenues of research and applications. Thanks to the maturity that attosecond physics has reached, together with the tremendous advance in material engineering and manipulation techniques, the age of atto-nanophysics has begun, but it is in the initial stage. We present thus some of the open questions, challenges and prospects for experimental confirmation of theoretical predictions, as well as experiments aimed at characterizing the induced fields and the unique electron dynamics initiated by them with high temporal and spatial resolution.
最近，两个新兴的研究领域，飞秒和纳观物理，开始结合在一起。飞秒物理研究的是超短激光脉冲与原子、分子或固体相互作用时发生的现象，这些激光脉冲的持续时间在飞秒和亚飞秒时间尺度内。激光诱导的电子动力学在时间尺度上自然发生，可达数百甚至数十飞秒（1 飞秒 = 1 阿秒 = 10 s），与光场相当。相比之下，氢原子 1s 轨道上电子的旋转约为 ∼152 阿秒。另一方面，第二个分支涉及到对介观系统，如固体、金属和电介质，进行纳米级精度的操控和工程。尽管纳米工程本身是一个广泛而成熟的研究领域，但与强激光物理的融合相对较新。在这篇进展报告中，我们全面介绍了短而强激光脉冲与纳米系统相互作用时发生的物理现象的实验和理论综述，例如金属和介电纳米结构。特别是，我们阐明了纳米尺度上的空间不均匀激光诱导场如何改变激光驱动的电子动力学。因此，这对诸如阈上电离和高阶谐波产生等关键过程有重要影响。对这些空间不均匀场与物质之间的耦合动力学的深入理解为新的研究和应用途径配置了一个很有前景的方向。由于飞秒物理已经达到了成熟的水平，再加上材料工程和操控技术的巨大进步，阿秒纳观物理的时代已经开始，但它仍处于初始阶段。因此，我们提出了一些开放性问题、挑战和前景，以便通过实验来验证理论预测，并进行实验来以高时间和空间分辨率来表征诱导场和由其引发的独特电子动力学。
