Armoured: Atomic R-matrix Method For Relativistic Dynamics

装甲：相对论动力学原子 R 矩阵方法

基本信息

批准号：
EP/P013953/1
负责人：
Hugo Willem Van Der Hart
金额：
$ 47.95万
依托单位：
Queen's University Belfast
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2017
资助国家：
英国
起止时间：
2017 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FP013953%2F1
关键词：
Armoured Atomic matrix Method Relativistic

项目摘要

In order to 'view' electrons in the atom, we need to be able to describe their motion on a time-scale comparable to the interactions themselves. This is akin to taking a photograph- the faster an object is moving, the shorter the exposure time required to capture it. The process of harmonic generation- where an electron in an atom is driven by a laser field in such a way as it re-emits high harmonics of the laser light- has provided a unique tool for probing atomic and molecular structure- allowing the imaging of molecular orbitals and even videos of chemical reactions taking place. While this field of attosecond physics (1 attosecond = 1 billionth of a billionth of a second) is well established, the theoretical description and computational models of the underlying processes are underdeveloped.In order to fully describe the fundamental dynamics of laser driven electrons in the atom we need to consider not just the effect of the laser field, nor even simply the net effect of the electrons, we must also describe the complex interactions between the many electrons. In order to facilitate this description in a computationally tractable way we have developed time-dependent R-matrix theory (TDRM), and associated computer codes. The theory makes use of an R-matrix division of configuration space in order to simplify the calculations without neglecting important multielectron effects. It is our intention to extend the TDRM technique to describe relativistic effects in ultrafast processes. The spin-orbit interaction, wherein an electron's intrinsic (spin) and orbital angular momenta interfere to change its behaviour, gives rise to fine structure splittings in atomic energy levels. The transitions of electrons between these levels occurs on a time-scale governed by the energy gap. For heavier elements such as krypton and xenon this time-scale is of the order of a few femtoseconds- and so dynamics can evolve within a laser pulse. By opening up new electron-emission channels, and changing the selection rules for electron transitions, the spin-orbit effect can significantly alter the fundamental processes of attosecond physics- ionisation, harmonic generation etc. Hence, interesting new dynamics can be observed on the atomic scale. By using the TDRM method we will be able to model these dynamics from first principles, thus giving an unparallelled insight into some of the most fundamental physical processes in atomic science.

为了在原子中“查看”电子，我们需要能够描述它们在与相互作用本身相当的时间尺度上的运动。这类似于拍摄照片 - 物体移动的速度越快，捕获它所需的曝光时间就越短。谐波产生的过程 - 原子中的电子是由激光场驱动的，既可以重新构成激光光的高谐波 - 为探测原子和分子结构的独特工具，允许对分子轨道的成像以及化学反应的视频进行成像。尽管已经确定了这个attosecond物理学领域（1亿分之十亿分之一），但基本过程的理论描述和计算模型欠发达的理论描述和计算模型。为了充分描述激光驱动电子的基本动态，我们还必须仅仅考虑各个效果，甚至不仅要构成Laser Field的效果，甚至还必须构成Laser Field的效果，因此我们需要效果，而我们的效果是我们的效果，我们的效果是肯定的。电子。为了以计算障碍的方式促进此描述，我们开发了时间依赖的R-Matrix理论（TDRM）和相关的计算机代码。该理论利用了配置空间的R-Matrix划分，以简化计算而无需忽略重要的多电极效应。我们打算扩展TDRM技术来描述超快过程中的相对论效应。自旋轨道相互作用，其中电子的固有（自旋）和轨道角动量会干扰其行为，从而导致原子能水平的精细结构分割。这些水平之间电子的过渡发生在能量差距控制的时间尺度上。对于诸如K k k和Xenon之类的重元素，此时间尺度是几个飞秒的顺序，因此动力学可以在激光脉冲中发展。通过打开新的电子发射通道，并改变电子过渡的选择规则，自旋轨道效应可以显着改变Attosend物理学的基本过程，谐波产生等。因此，可以在原子量表上观察到有趣的新动力学。通过使用TDRM方法，我们将能够从第一原理中对这些动态进行建模，从而对原子科学中一些最基本的物理过程提供无与伦比的见解。