Supervisors: Andreas Döpp (Ludwig Maximilian University of Munich) & Charlotte Palmer (Queen’s University of Belfast)
At the Centre for Advanced Laser Applications (CALA) of LMU Munich, researchers use the world's most powerful lasers for cutting-edge research at the interface of fundamental science and applications. Our groups focus on the generation of novel particle and photon beams from laser-driven sources, as well as their emerging applications. This work spans from studying ultrahigh-intensity laser interaction with plasmas to continuous improvement of drive laser pulse parameters through advanced laser development.
Laser-plasma acceleration represents a revolutionary technology that drastically downsizes particle accelerators. At its core, the technology relies on just two key components: a high-intensity laser pulse and a gaseous target that becomes ionized into plasma. The interplay between these components creates a plasma wakefield—a microscopic accelerating structure thinner than a hair and extending about a millimeter in length. Our group has recently demonstrated significant advances in optimizing these accelerators using Bayesian methods, achieving unprecedented control over beam parameters and stability [1].
The performance and optimization of laser-plasma accelerators fundamentally depends on our understanding of both the laser pulse and the plasma response. Over the past years, we have made important advances in laser diagnostics [2,3], culminating in our ability to measure the complete vector field of the driving laser within a single shot [4]. This achievement represents a crucial milestone, as it provides us with comprehensive information about one half of the laser-plasma interaction. However, for a complete model and truly optimal control of the acceleration process, we need similar improvements in plasma diagnostics. Even advanced techniques using few-cycle laser pulses and electron bunches as probes can only capture two-dimensional projections of the plasma structure, leaving its three-dimensional evolution largely unexplored.
This project aims to complete the diagnostic picture by developing novel plasma measurement techniques through Bayesian Experimental Design (BED). Rather than treating measurement as a passive process, BED provides a rigorous framework for maximizing information gain in each experimental observation. Our approach combines tomographic principles with BED to encode and extract maximum information from different observation angles on a single detector. With comprehensive diagnostics of both the laser and plasma components, we will be able to build more accurate models of the complete acceleration process. This will enhance our Bayesian optimization approaches by providing detailed, shot-to-shot measurements of both the driving laser and the plasma response, enabling us to better understand their interaction and identify optimal operating conditions. The combination of advanced laser diagnostics and novel plasma measurements creates a complete framework for understanding and controlling laser-plasma accelerators.
Success in this project will bridge the gap between experimental observations and numerical simulations of laser-plasma accelerators, providing unprecedented insight into the acceleration process and enabling more efficient optimization of these novel accelerators. Beyond accelerator physics, our novel framework for information-optimal experimental design has applications in fields ranging from volumetric microscopy to medical imaging, opening possibilities for future technological transfer and commercialization.
Expected Results
- Demonstration of single-shot tomographic plasma measurements
Planned secondments
- Secondments are possible among our close collaboration partners at University of Oxford (UK), Laboratoire d’Optique Appliquée (France), Universidad de Salamanca (Spain) and the Kansai Photon Science Institute (Japan)