Laser-guided electronic acceleration optimization

The interaction between laser and matter is at the forefront of new investigations into fundamental physics, as well as providing a potential foundation for new technological innovations. One of the initiatives leading this investigation is the Extreme Light Infrastructure Nuclear Physics (ELI-NP) project. Here the project’s High-Power Laser System (HPLS), the most powerful laser in the world, is just one of the tools that drive electronic acceleration with lasers, Direct Laser Acceleration (DLA). In a new article published in EPJ D, Etele Molnar, ELI-NP, Bucharest, and co-authors study and review the characteristics of electronic acceleration in vacuum caused by the maximum power laser pulses obtainable today in search of the key to maximum net energy gain.

In particular, the authors calculate the optimal values ​​of the laser beam required to obtain the maximum electronic energy for different levels of laser power. They observe that fine-tuning certain aspects of a laser such as its beam belt – the point where a laser beam has its minimum beam – can favorably increase the maximum acceleration of electrons in vacuum for both linearly and polarized lasers. circularly.

As might be expected, Molnar and colleagues find that the net energy of electrons, and hence their acceleration, is increased with increased laser power for beams with optimal beam life. The article describes an average electron energy gain of a few MeV in full pulse interactions, where the highest electron energy is about 160 MeV. In other cases, such as half-pulse interactions, however, the authors state that these energy gains are nearly an order of magnitude larger, reaching up to 1 GeV.

In terms of future research, the paper proposes other potential directions. For example, the researchers suggest that a study focusing on direct laser acceleration with higher Laguerre gaussian modes – circularly symmetrical beam profiles or lasers with cylindrical symmetrical cavities – should follow the current paper.