Semi-classical models for ultra-fast multi-electron phenomena in intense electro-magnetic laser fields

阿托科学是21世纪最大的科学挑战之一。阿秒和亚飞秒是原子和分子电离和分裂过程中多电子效应的自然时标。这项拟议的研究将探索相关多电子动力学背后的物理机制，并设计探测/控制这些机制的方案。关联电子动力学对阿秒技术具有重要意义。例如，从分子中提取的电子携带着确定电子分子轨道和原子核位置的信息，从而为分子成像铺平了道路。此外，这项拟议的工作将探索磁场和量子干涉对阿秒过程的影响。这些效应对于充分理解阿秒脉冲的产生和光电子全息照相等现象是至关重要的。本工作的总体目标是研究超短和超强近红外和中红外激光脉冲在原子和多中心分子中触发的多电子电离过程中的阿秒现象、磁场和干涉效应。快速的实验进展将这些现象放在了阿托斯学的前沿。迫切需要新的理论工具来应对这一领域面临的挑战。作为对这一探索的回应，我提供了新颖、高效和复杂的半经典方法，这些方法比量子力学方法快得多，并允许对物理机制进行重大洞察。这些半经典技术适用于通过长程库仑力的电离过程。使用这些技术，我将解决Attoscience面临的一些最基本的问题。我的目标是：1)利用非偶极效应来研究近红外和中红外激光脉冲驱动的双电子原子和双原子分子中电子和离子之间的光子动量分享；3)利用非偶极效应和干涉效应来研究中红外激光脉冲驱动的双电子原子和双原子分子中的“受阻”电离和非顺序双电离。4)研究近红外激光脉冲驱动的双电子和三电子三中心分子中的非顺序和“受挫”电离。

Attoscience is one of the great scientific challenges of the 21st century. Attoseconds and sub-femtoseconds are the natural time scale for multi-electron effects during the ionization and break-up of atoms and molecules. The proposed research will explore the physical mechanisms underlying correlated multi-electron dynamics and devising schemes to probe/control these mechanisms. Correlated electron dynamics is of fundamental interest to attosecond technology. For instance, an electron extracted from a molecule carries information determining the electronic molecular orbital and position of the nuclei, thus paving the way for molecular imaging. Moreover, the proposed work will explore magnetic field and quantum interference effects on attosecond processes. These effects are crucial for fully understanding many phenomena, such as the generation of attosecond pulses and holography with photoelectrons.The overall aim of the proposed work is to explore attosecond phenomena, magnetic field and interference effects during multi-electron ionization in atoms and multi-center molecules triggered by ultra-short and ultra-strong near-infrared and mid-infrared laser pulses. The rapid experimental advances place these phenomena at the forefront of Attoscience. New theoretical tools are urgently needed to address the challenges facing this field. In response to this quest, I offer novel, efficient and sophisticated semi-classical methods that are much faster than quantum-mechanical ones and that allow for significant insights into the physical mechanisms. These semi-classical techniques are appropriate for ionization processes through long-range Coulomb forces. Using these techniques, I will address some of the most fundamental problems facing Attoscience. My objectives are:1) Account for non-dipole effects to explore photon momentum sharing between electrons and ions in two-electron atoms and diatomic molecules driven by near-IR and mid-IR laser pulses.3) Account for non-dipole and interference effects to explore "frustrated" ionization and non-sequential double ionization in two-electron atoms and diatomic molecules driven by mid-IR laser pulses.4) Explore non-sequential and "frustrated" ionization in two- and three-electron three-center molecules driven by near-IR laser pulses.