"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."