Correlated electron dynamics: from attoscience to nanophysics

强扰动下复杂系统的动力学结合了理论物理中最具挑战性的两个问题，即少体/多体物理和非摄动动力学。到目前为止，几乎没有什么理论工具可以解决这个问题。在过去的几年里，Brabec博士的团队开发了一种新的方法，称为多组态依赖时间的Hartree-Fock(MCTDHF)。MCTDHF方法是第一个在适当考虑关联的情况下计算强微扰下少电子系统动力学的方法。由此，它开启了从理论上研究迄今无法获得的广泛相关的少电子现象的机会。在这项研究提案中，MCTDHF将用于解决以下三个问题。(I)强X射线辐射如何与物质相互作用？高强度X射线源有望在包括生命科学在内的广泛领域得到开创性的应用。理解上述问题是回答目标是否可以在被强X射线辐射摧毁之前测量的第一步。(2)激光场的存在如何增强电子碰撞电离？强激光脉冲与物质的相互作用产生了等离子体。突出的例子是激光微加工和激光驱动的电子和X射线源。理解激光辅助碰撞电离对于正确描述上述过程是至关重要的。(Iii)量子点中的关联少电子动力学是如何发生的？更好地了解这些过程将有助于推动分子、纳米电子学和量子计算领域的发展。这里涉及的三个课题属于加拿大的关键研究领域，如光子学和纳米物理学。这项研究使用了一种新的工具，将引起国际关注。这将加强加拿大在上述关键领域的国际地位，从而推动技术发展和经济增长。

Dynamics in complex systems subjected to strong perturbations combines two of the most challenging problems of theoretical physics, which are few-/many-body physics and non-perturbative dynamics. To date, there exist little theoretical tools that can handle this problem. Over the past few years the group of Dr. Brabec has developed a novel approach called multi-configuration time-dependent Hartree-Fock (MCTDHF). MCTDHF is the first method that can calculate the dynamics of few-electron systems in the presence of strong perturbations, taking properly account of correlation. Therewith, it opens the opportunity to theoretically investigate a wide spectrum of correlated few electron phenomena that were not accessible so far.In this research proposal MCTDHF will be used to address the following three questions. (i) How does intense x-ray radiation interact with matter?High intensity x-ray sources promise ground breaking applications in a wide range of areas, including life sciences.Understanding of the above question presents a first step to answering the question whether targets can be measured before they are destroyed by intense x-ray radiation. (ii) How does the presence of a laser field enhance electron impact ionization? The interaction of intense laser pulses with matter creates a plasma. Prominent examples are laser micromachining and laser driven electron and x-ray sources. Understanding of laser assisted impact ionization is essential for a correct description of the above processes. (iii) How does correlated few electron dynamics in quantum dots take place? A better understanding of these processes will help to advance the fields of molecular-, nano-electronics, and quantum computation.The three topics tackled here fall in Canadian key research areas, such as photonics and nanophysics. The research utilizes a novel tool that will attract international attention. This will strengthen Canada's international standing in the above key areas, therewith fuelling technological development and economic growth.