Ultra-fast three and four-electron dynamics in intense electro-magnetic laser fields

超短和超强激光脉冲提供了一台令人印象深刻的相机，可以进入电子运动的世界。阿秒和亚飞秒是原子和分子电离和分裂过程中多电子动力学的自然时间尺度。拟议工作的总体目标是研究阿秒现象、相关电子动力学的路径以及由强近红外和中红外激光脉冲触发的原子和分子中的三电子和四电子电离中光的磁场引起的效应。关联电子动力学对阿秒技术具有重要意义。例如，从原子或分子中提取的电子携带着探测离子体系时空性质的信息，分辨率为埃，精度为阿秒，为光电子全息术铺平了道路。此外，研究光在相关多电子过程中的磁场效应对于理解各种化学和生物过程，如驱动手性分子的响应是至关重要的。手性分子不能叠加到它们的镜像上，而且由于它们在自然界中含量丰富，因此特别令人感兴趣。这项拟议的研究将探索极具挑战性的超快现象，涉及三电子和四电子动力学，以及受驱动原子中光的磁场以及受驱动的双中心和三中心分子分裂过程中的影响。我们将研究这些现象背后的物理机制，并设计出探测和控制它们的方案。由于阿秒技术的快速进步，探索这些超快现象构成了一个科学前沿。这些基本过程在很大程度上是未被探索的，因为大多数理论研究都是在一个不考虑光的磁场的框架内进行的。此外，相关的三电子和四电子逃逸目前超出了量子力学技术的能力范围。因此，迫切需要新的理论工具来解决意识科学面临的挑战。作为对这一探索的回应，我们将开发新的、高效的和尖端的半经典方法，这些方法比量子力学方法快得多，允许对物理机制有重要的见解，对实验结果表示赞赏，并预测新的超快现象。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，我们将解决意识科学面临的一些最基本的问题。我们的目标是：1)识别和时间分辨由近红外和中红外激光脉冲驱动的原子中相关三电子动力学的新路径。2)探索在原子电离过程中相关的两个和三个电子逃逸以及由近红外和中红外激光脉冲驱动的两个和三个中心分子中由于光的磁场的影响，近红外和中红外激光脉冲要么是线偏振的，要么是椭圆偏振的，或者是由矢量光束驱动的，也就是“扭曲”的激光场，一种像螺旋开瓶器一样旋转的耐人寻味的光的形式。3)控制相关的多电子电离和通过使用双色激光场或矢量束在四个活跃电子的三中心分子中形成高度激发的里德堡态。

Ultra-short and ultra-intense laser pulses provide an impressive camera into the world of electron motion. Attoseconds and sub-femtoseconds are the natural time scale of multi-electron dynamics during the ionization and break-up of atoms and molecules. The overall aim of the proposed work is to investigate attosecond phenomena, pathways of correlated electron dynamics and effects due to the magnetic field of light in three and four-electron ionization in atoms and molecules triggered by intense near-infrared and mid-infrared laser pulses. Correlated electron dynamics is of fundamental interest to attosecond technology. For instance, an electron extracted from an atom or molecule carries information for probing the spatio-temporal properties of an ionic system with angstrom resolution and attosecond precision paving the way for holography with photoelectrons. Moreover, studies of effects due to the magnetic field of light in correlated multi-electron processes are crucial for understanding a variety of chemical and biological processes, such as the response of driven chiral molecules. Chiral molecules are not superimposable to their mirror image and are of particular interest, since they are abundant in nature. The proposed research will explore highly challenging ultra-fast phenomena involving three and four-electron dynamics and effects due to the magnetic field of light in driven atoms and during the break-up of driven two and three-center molecules. We will investigate the physical mechanisms that underly these phenomena and devise schemes to probe and control them. Exploring these ultra-fast phenomena constitutes a scientific frontier due to the fast advances in attosecond technology. These fundamental processes are largely unexplored since most theoretical studies are developed in a framework that does not account for the magnetic field of light. Moreover, correlated three and four-electron escape is currently beyond the reach of quantum mechanical techniques. Hence, new theoretical tools are urgently needed to address the challenges facing attoscience. In response to this quest, we will develop novel, efficient and cutting-edge semi-classical methods that are much faster than quantum-mechanical ones, allow for significant insights into the physical mechanisms, compliment experimental results and predict novel ultra-fast phenomena. These semi-classical techniques are appropriate for ionization processes through long-range Coulomb forces. Using these techniques, we will address some of the most fundamental problems facing attoscience. Our objectives are:1) Identify and time-resolve novel pathways of correlated three-electron dynamics in atoms driven by near-infrared and mid-infrared laser pulses.2) Explore effects due to the magnetic field of light in correlated two and three-electron escape during ionization in atoms as well as in two and three-center molecules driven by near-infrared and mid-infrared laser pulses that are either linearly or elliptically polarized or by vector beams, i.e. "twisted" laser fields, an intriguing form of light that twists like a helical corkscrew.3) Control correlated multi-electron ionization and the formation of highly exited Rydberg states in four-active-electron three-center molecules by employing two-color laser fields or vector beams.