Attosecond observation and control of collective electron dynamics in complex matter

自2001年首次实现以来，阿秒（1 as = 10- 18 s）激光脉冲的产生和表征有了显著的进展。现在有两个主要的工具可以用来探索超快物理。第一个是通过波形控制激光场来控制电子运动的能力。第二个是单个阿秒脉冲的可用性，它可以用来实时探测电子运动。我们将首次使用这些工具来研究纳米和介观系统中的集体电子动力学。集体电子动力学对于纳米粒子的光学响应特别重要。这些材料具有巨大的根本利益，并且具有广泛的应用，从医学和生物学中的标记物到化学中的催化剂再到量子计算机。对纳米粒子的研究动机与基于尺寸和形状定制其动力学行为的可能性有关。这是第一次，我们将探索电子动力学的纳米粒子和集群与亚飞秒时间分辨率。通过这种方式，我们可以获得这些材料在自然界中发生的时间尺度上的集体电子特性的信息。我们的工作可以对纳米等离子体器件的发展产生巨大影响。

After their first realization in 2001, the generation and characterization of attosecond (1 as = 10-18s) laser pulses has been significantly advanced. Two major tools are now at hand that can be used to explore ultrafast physics. The first is the ability to control electronic motion via waveform-controlled laser fields. The second is the availability of single attosecond pulses that can be used to probe electronic motion in real-time. We will use these tools for the first time to study collective electron dynamics in nanoscopic and mesoscopic systems. Collective electron dynamics are of particular importance for the optical response of nanoparticles. These materials are of huge fundamental interest and have wide applications ranging from markers in medicine and biology over catalysts in chemistry to quantum computers. The motivation for studies on nanoparticles is related to the possibility of tailoring their dynamical behavior on the basis of size and shape. For the first time, we will explore electron dynamics in nanoparticles and clusters with sub-femtosecond time resolution. This way, we can gain information on the collective electronic properties of these materials on a timescale on which they occur in nature. Our work can have a huge impact on the development of nanoplasmonic devices.