Prospects for performing tests of strong-field quantum electrodynamics with high-intensity lasers

Abstract

High-intensity lasers generate exceptionally strong electromagnetic fields and, when collided with ultrarelativistic electrons, provide a promising testbed for exploring strong-field quantum electrodynamics (SFQED). Modern laser-electron colliders can access regimes where SFQED effects begin to emerge, and qualitative observations of the underlying quantum processes have been achieved whereas quantitative analyses, as well as the detection of deeper quantum nonlinearities, are yet to be done. The challenges are how to reach such extreme interaction regimes with current laser and accelerator technology, and how to distinguish the relatively rare events occurring in the strong-field region, which are often limited by premature electron energy loss and unavoidable shot-to-shot variations. In sufficiently extreme conditions, electron-positron pair production initiates QED cascades, producing large numbers of low-energy particles and photons that mask the signatures of interest. In this thesis, I present theoretical and numerical studies of alternative laser-electron collision geometries and statistical techniques aimed at overcoming these limitations in upcoming SFQED experiments. I derive a strategy to isolate SFQED emissions of interest and propose a focusing geometry that maximizes the attainable quantum nonlinearity for a given laser power. I further investigate multi-pulse interaction layouts in which electrons traverse the focal region of tightly focused radiation to enhance the signal-to-noise ratio of rare events. Finally, I introduce a Bayesian inference framework for estimating parameters in SFQED models under experimental fluctuations. These findings demonstrate a reduction in the number of experimental shots required to observe SFQED signatures, an experimental reach into extreme regimes accessible to near-future laser facilities, and possibilities to probe deep quantum nonlinearities while mitigating the effects of QED cascades.