Theoretical and numerical investigation of collective effects in extreme laser-plasma interaction

拟议的研究项目侧重于在10^22-10^24 W/cm^2范围内的超高激光强度下激光与物质相互作用的物理理论和数值研究。这些强度将很快在多拍瓦激光设备上实现，例如800meo极光基础设施（ELI）和apolon - 10p。这些设施将使探索新的基本物理过程，如辐射反应、相对论电子动力学、电子-正电子对的产生和相对论离子的产生成为可能。当激光强度超过10^22 W/cm^2时，电子产生显著的同步辐射，产生强烈影响光子发射光谱和整个等离子体动力学的辐射反作用力。由于所涉及的强电磁场，量子效应将变得重要的激光强度超过10^23W/cm^2，导致产生大量的电子-正电子对。我的建议旨在从理论上和数值上探索这些建议的基础物理。这些结果将用于指导使用这些新型超强激光系统的相关实验的设计和解释。提出的研究项目开辟了受量子电动力学（QED）过程影响的超相对论等离子体的新方向。例如，迄今为止，等离子体离子对高能同步辐射和电子-正电子对产生的作用知之甚少，从未在实验中进行过探索。通常认为，短激光脉冲与等离子体的相互作用是由电子动力学决定的，而离子由于它们反应的时间尺度较长而起次要作用。虽然这对于较低的激光强度来说可能是正确的，但在超相对论性激光脉冲的情况下，情况变得更加复杂，因为它的颤振电子能量可以与离子静止质量相媲美。离子响应驱动的集体效应将在半经典等离子体和量子等离子体中进行研究。在这个研究项目中，我们将建立一个激光能量吸收的离子响应动力学理论。未来的实验，将测试理论和模拟的预测，也将被设计出来。该项目涉及与英国和欧洲高场激光等离子体相互作用物理学领域的许多领先研究人员合作。它还涉及与斯特拉斯克莱德大学的一个实验小组以及ELI-NP高场科学工作组的密切合作。

The proposed research project focuses on theoretical and numerical investigations of the physics of laser-matter interaction at ultra-high laser intensities, in the range 10^22-10^24 W/cm^2. These intensities will soon be achievable at multi-petawatt laser facilities, such as the 800MEuro extreme light infrastructure (ELI) and APOLLON-10P. These facilities will enable the exploration of new fundamental physical processes such as radiation reaction, relativistic electron dynamics, electron-positron pair production and the generation of relativistic ions. Electrons produce significant synchrotron radiation at laser intensities above 10^22 W/cm^2 giving rise to the radiation reaction force that strongly affects the photon emission spectrum and the overall plasma dynamics. Due to the intense electromagnetic fields involved, quantum effects will become important for laser intensities above 10^23W/cm^2, resulting in the production of copious amounts of electron-positron pairs. My proposal aims to explore the underpinning physics of these proposes theoretically and numerically. The results will be used to guide the design and interpretation of related experiments using these new ultraintense laser systems.The proposed research project opens up new directions in ultra-relativistic plasmas that are subject to quantum electrodynamics (QED) processes. For example, to date, the role of the plasma ions on the high energy synchrotron radiation and electron-positron pair production, is poorly understood and has never been explored experimentally. It is often suggested that the interaction of a short laser pulse with plasmas is dominated by the electron dynamics and that the ions play a secondary role due to the longer timescales over which they react. Although this may be true for lower laser intensities, the situation becomes more complicated in the case of ultra-relativistic laser pulses for which the quiver electron energy could be comparable with the ion rest mass. The collective effects driven by the ion response will be investigated in both semi-classical plasmas and quantum plasmas. A kinetic theory of laser energy absorption accounting for ion response will be developed over this proposed research project. Future experiments, which will test the predictions of the theory and simulations, will also be designed.The project involves collaboration with a number of leading researchers in high field laser-plasma interaction physics, both in the UK and in Europe. It also involves a close collaboration with an experimental team at the University of Strathclyde and with the ELI-NP high field science working group.