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个令人印象深刻的相机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。本研究的总体目的是研究近红外和中红外激光脉冲触发原子和分子中三电子和四电子电离的阿秒现象、相关电子动力学途径和光磁场效应。相关电子动力学是阿秒技术的基础。例如，从原子或分子中提取的电子携带着探测离子系统时空特性的信息，具有埃分辨率和阿秒精度，为光电子全息术铺平了道路。此外，研究光磁场对相关多电子过程的影响对于理解各种化学和生物过程至关重要，例如驱动手性分子的响应。手性分子与它们的镜像是不重叠的，因为它们在自然界中很丰富，所以特别有趣。该研究将探索极具挑战性的超快现象，包括三电子和四电子动力学，以及由驱动原子中的光磁场和驱动二中心和三中心分子分裂引起的效应。我们将研究这些现象背后的物理机制，并设计方案来探测和控制它们。由于阿秒技术的快速发展，探索这些超快现象构成了一个科学前沿。由于大多数理论研究都是在一个没有考虑光磁场的框架中发展起来的，因此这些基本过程在很大程度上没有被探索过。此外，相关的三电子和四电子逸出目前超出了量子力学技术的范围。因此，迫切需要新的理论工具来解决能源科学面临的挑战。为了响应这一探索，我们将开发新颖，高效和前沿的半经典方法，这些方法比量子力学方法快得多，允许对物理机制的重要见解，补充实验结果并预测新的超快现象。这些半经典技术适用于通过远距离库仑力的电离过程。使用这些技术，我们将解决一些最基本的问题，面临的科学。我们的目标是：1)识别和时间分辨近红外和中红外激光脉冲驱动原子中相关三电子动力学的新途径。2)探索在线性或椭圆偏振的近红外和中红外激光脉冲或矢量光束驱动下，在原子电离过程中相关的二、三电子逸出以及二、三中心分子中由于光的磁场而产生的效应。“扭曲的”激光场，一种有趣的光形式，像螺旋开瓶器一样扭曲。3)利用双色激光场或矢量光束控制四活性电子三中心分子的相关多电子电离和高激发态的形成。

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.