近QED强度激光与等离子体相互作用的理论和粒子模拟研究

With the development of high power PW class lasers, unprecedented extreme physical conditions are created in laboratories. The laser-matter interaction becomes highly nonlinear and enters the quantum electrodynamics plasma (QED-plasma) regime. In this project, we focus on the interaction of laser and plasma in near QED regime, and carry out theoretical investigations and particle-in-cell simulations of QED physical processes such as radiation trapping of electrons, γ-ray emission and electron-positron pairs creation. We will investigate the influence of the laser intensity, the polarization state and the space pattern on the electron dynamics, and the influence of the plasma environment on the QED cross section of the electron radiation. The new mechanism of laser energy absorption in near QED regime will be explored. The physical mechanism of laser focusing and electron trapping in conical target configurations filled with near-critical-density plasma will be studied. With the study of physical mechanisms of high-energy γ-ray emission and electron-positron pairs creation, we will propose new schemes to produce high-brightness γ-ray and energetic dense positron beams. The study of this project may provide a reference for the physical experiment design and the table-top high energy radiation source based on high power PW class lasers in the future.

拍瓦级高功率激光器的发展在实验室中创造出前所未有的极端物理条件，把激光与物质相互作用推进到量子电动力学等离子体的范畴。本项目针对近QED强度的激光与等离子体相互作用，对电子的辐射捕获、γ射线及正负电子对产生等QED物理过程开展理论和粒子模拟研究。研究激光场的强度、极化态、空间模式等对电子动力学的影响，以及等离子体环境对电子辐射QED截面的影响，探索超强激光能量吸收的新机制。研究充有近临界密度的锥靶构型中激光聚焦和电子捕获的物理机制。研究高能γ射线及正负电子对产生的物理机制，提出产生高亮度γ射线及高能稠密正电子束的方案。本项目的研究有可能为拍瓦级激光装置上的物理实验设计以及台面型高能辐射源的方案提供参考。

近年来，拍瓦级超短超强激光装置得到迅速发展，在实验室中创造出前所未有的极端物理条件，把激光与物质相互作用推进到量子电动力学等离子体的范畴。本项目采用理论和数值模拟的方法，对近QED强度激光与等离子体相互作用中的电子动力学、辐射阻尼效应、粒子加速及辐射机制展开研究，提出了基于非线性汤姆逊散射的涡旋伽马辐射源、激光与多通道波导型表面调制靶相互作用产生高产额正电子束、百拍瓦激光与金锥靶相互作用产生GeV重离子束、以及基于尾波场类Betatron辐射产生高能伽马辐射源等物理方案。本项目的研究有可能为拍瓦级激光装置上的物理实验设计以及台面型高能辐射源的方案提供参考。.