Nonlinear laser-duration and plasma-density interplay

Characterize the nonlinear interplay between laser duration and plasma density in direct-laser-acceleration interactions, including its effect on electron-to-laser conversion efficiency, to determine the conditions under which the conversion efficiency can be enhanced.

Background

The paper presents optimized direct laser acceleration (DLA) in gas targets as a method for producing high-charge, GeV-scale electron bunches that can generate dense electron–positron beams and muons. The authors note that the accelerated electron energy distribution and conversion efficiency depend on the laser and plasma parameters, including the laser duration and plasma density.

Although the paper reports that varying the plasma density changes the balance between electron energy and bunch density, it does not resolve how the nonlinear interaction between laser duration and plasma density controls or enhances the laser-to-electron conversion efficiency. Establishing this relationship would support further optimization of DLA-driven secondary-particle sources.