Attosecond Electron Dynamics in Molecular and Condensed Phase Systems

这是一项高级研究计划，具有极高的科学影响力，并应用于对英国具有重要战略意义的领域，如可再生能源和生物分子技术。其目的是开发和应用尖端实验和理论工具的组合，以100阿秒的时间和纳米空间分辨率观察和模拟分子和凝聚相物质的动力学。我们将实现的时间分辨率比目前测量较大分子和凝聚态物质的最先进水平高出两个数量级。科学史表明，每当测量能力出现如此大的改进时，重大新的突破是不可避免的。例如，最近发现，在物质的关键分子构件中突然出现电子激发之后，会发生普遍的初级事件--电荷跨越纳米的亚飞秒到极少飞秒的迁移。这种电荷迁移预计在触发后续的核动力学和控制化学变化方面极其重要，但用现有方法观察到的速度太快。拟议的研究方案将利用组装小组开发的世界领先的实验和理论工具来研究电荷迁移和其他以前未曾探索过的阿秒尺度过程的性质。我们将开创凝聚相物质和大分子研究的先河，包括生物分子的构建块。从这项研究中获得的知识将导致对物质电子激发的第一时刻的新理解，并最终带来优化人工光捕获、分子电子器件和生物分子分析的新方法。美国能源部已将电子水平上的物质成像和控制动力学，特别是远离平衡的物质，以及理解量子相干在分子和纳米级组装中的作用，确定为基础能源科学的五大科学挑战的关键组成部分(Phys.Today，2008年7月，28-33页)。我们的方案将使解决这些问题所需的实验和理论的协调努力和紧密联系成为可能。英国在这一领域拥有独一无二的世界领先机会，因为我们组建了一支非凡的团队，他们掌握了领导这一新的重要科学领域所需的所有技术和理论工具。我们的计划将利用我们已经开始开发的两种新型测量：高次谐波产生(HHG)光谱和阿秒泵浦-探测光谱，并将它们应用于大分子和凝聚相中阿秒电子动力学的测量。这是一项艰巨的挑战，将在实验和理论上开辟新的领域。我们将通过协调和平衡的方案来应对这一挑战，该方案将汇集阿秒物理、量子化学、分子结构和动力学、超快和强场科学、纳米尺度和等离子体物理的理论和实验专业知识。该方案由4个相互关联的项目组成，每个项目都对最终的研究结果做出了重大贡献：项目1：高次谐波产生(HHG)光谱学项目2：阿秒泵浦-探测光谱学项目3：电荷迁移和核动力学的耦合项目4：探测凝聚阶段的阿秒动力学。

This is a programme of advanced research with potential for extremely high scientific impact and applications to areas of great strategic importance to the UK, such as renewable energy and biomolecular technology. The aim is to develop and apply a combination of cutting-edge experimental and theoretical tools to observe and model dynamics in molecules and condensed phase matter with 100 attosecond temporal and nanometre spatial resolutions. The temporal resolution we will achieve is two orders of magnitude beyond the current state-of-the-art for measurements in larger molecules and condensed matter. The history of science shows that whenever such large improvements in measurement capability occur major new breakthroughs are inevitable. For instance, it has recently emerged that sudden electronic excitation in key molecular building blocks of matter is followed by a universal primary event - sub-femtosecond to few femtosecond migration of electric charge across nanometres. This charge migration, expected to be extremely important in triggering subsequent nuclear dynamics and so controlling chemical change, is too fast to be observed with existing methods. The proposed research programme will apply the world-leading experimental and theoretical tools developed by the assembled team to study the nature of charge migration and other previously unexplored attosecond-scale processes. We will pioneer the investigation in both condensed phase matter and large molecules including the building blocks of biomolecules. The knowledge gained from this research will lead to a new understanding of the first moments in the electronic excitation of matter and ultimately to, for example, new approaches for optimising artificial light harvesting, molecular electronic devices and biomolecular analysis.Imaging and controlling dynamics of matter at the level of electrons, especially far from equilibrium, and understanding the role of quantum coherence in molecules and nanoscale assemblies have been identified by the US Department of Energy as key components of five grand scientific challenges to basic energy sciences (Phys.Today, July 2008, p28-33). Our programme will enable the concerted effort and close linking of experiment and theory needed to address these questions. The UK has a unique opportunity for world leadership in this area, as we have assembled an exceptional team that commands all of the technical and theoretical tools required to lead this new and important area of science.Our programme will exploit two new types of measurements that we have already begun to develop: high harmonic generation (HHG) spectroscopy and attosecond pump-probe spectroscopy, and will apply them to the measurement of attosecond electron dynamics in large molecules and the condensed phase. This is a formidable challenge that will open new frontiers both experimentally and theoretically. This challenge will be met by our coordinated and balanced programme that will bring together theoretical and experimental expertise in attosecond physics, quantum chemistry, molecular structure and dynamics, ultrafast and intense-field science, nanoscale and plasma physics.The programme is structured into 4 interlinked projects, each of which makes a major contribution to the eventual research outcomes: Project 1: High harmonic generation (HHG) spectroscopy Project 2: Attosecond pump-probe spectroscopy Project 3: Coupling of charge migration and nuclear dynamics Project 4: Probing attosecond dynamics in the condensed phase .