Optimization of e(+)/e(-) pair yield during the interaction of a Doppler-boosted laser with a solid-density plasma

The interaction of a Doppler-boosted laser with a solid-density plasma is investigated with two-dimensional particle-in-cell simulations, with special attention paid to the influences of laser incident angle on the yield of e+/e- pairs. With normal laser incidence, it is found that parts of plasma electrons are accelerated by the reflected laser and radiate high-energy.-photons, which further make nearly head-on collisions with the subsequent incoming laser pulses. The nonlinear quantum parameters of the produced photons can reach 4.6, and the yield of e(+)/e(-) pairs increases by a factor of 4 compared to an incident angle of 45.. The optimization is easy to implement and can improve the signal-to-noise ratio in the experiments. (c) 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).