10 January 2024 | Itamar Cohen, Talia Meir, Kavin Tangtartharakul, Lior Perelmutter, Michal Elkind, Yonatan Gershuni, Assaf Levanon, Alexey V. Arefiev, Ishay Pomerantz
This article discusses the direct laser acceleration (DLA) method, which is used to generate high-energy particle beams in university-scale laboratories. DLA involves ionizing the target material with the leading part of the laser pulse, forming a positively charged ion plasma channel into which electrons are injected and accelerated. The study reveals that for efficient DLA, a target material with a sufficiently high atomic number is required to maintain the injection of ionization electrons at the peak intensity of the pulse when the DLA channel is already formed. The researchers experimentally and numerically demonstrated that when the atomic number is too low, the target is depleted of its ionization electrons prematurely. Applying this understanding to multi-petawatt laser experiments is expected to result in increased neutron yields, which are crucial for various research and applications. The study also highlights the importance of using high-Z plasma plumes, such as those created by pre-explooding thin foils of gold, to achieve higher electron temperatures and more efficient DLA. The findings have implications for enhancing the performance of DLA in generating high-energy particle beams and improving neutron yields for various scientific and industrial applications.This article discusses the direct laser acceleration (DLA) method, which is used to generate high-energy particle beams in university-scale laboratories. DLA involves ionizing the target material with the leading part of the laser pulse, forming a positively charged ion plasma channel into which electrons are injected and accelerated. The study reveals that for efficient DLA, a target material with a sufficiently high atomic number is required to maintain the injection of ionization electrons at the peak intensity of the pulse when the DLA channel is already formed. The researchers experimentally and numerically demonstrated that when the atomic number is too low, the target is depleted of its ionization electrons prematurely. Applying this understanding to multi-petawatt laser experiments is expected to result in increased neutron yields, which are crucial for various research and applications. The study also highlights the importance of using high-Z plasma plumes, such as those created by pre-explooding thin foils of gold, to achieve higher electron temperatures and more efficient DLA. The findings have implications for enhancing the performance of DLA in generating high-energy particle beams and improving neutron yields for various scientific and industrial applications.