用多拍瓦激光在低密度等离子体中实现直接激光加速：通往高电荷、GeV级电子束团之路。

Direct Laser Acceleration in Underdense Plasmas with Multi-PW Lasers: A Path to High-Charge, GeV-Class Electron Bunches.

作者信息

Babjak R, Willingale L, Arefiev A, Vranic M

机构信息

GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon 1049-001, Portugal.

Institute of Plasma Physics, Czech Academy of Sciences, Za Slovankou 1782/3, 182 00 Praha 8, Czechia.

出版信息

Phys Rev Lett. 2024 Mar 22;132(12):125001. doi: 10.1103/PhysRevLett.132.125001.

DOI:10.1103/PhysRevLett.132.125001

PMID:38579225

Abstract

The direct laser acceleration (DLA) of electrons in underdense plasmas can provide hundreds of nC of electrons accelerated to near-GeV energies using currently available lasers. Here we demonstrate the key role of electron transverse displacement in the acceleration and use it to analytically predict the expected maximum electron energies. The energy scaling is shown to be in agreement with full-scale quasi-3D particle-in-cell simulations of a laser pulse propagating through a preformed guiding channel and can be directly used for optimizing DLA in near-future laser facilities. The strategy towards optimizing DLA through matched laser focusing is presented for a wide range of plasma densities paired with current and near-future laser technology. Electron energies in excess of 10 GeV are accessible for lasers at I∼10^{21} W/cm^{2}.

摘要

在低密度等离子体中对电子进行直接激光加速（DLA），利用现有的激光可将数百纳库的电子加速到接近吉电子伏特的能量。在此，我们展示了电子横向位移在加速过程中的关键作用，并利用它来解析预测预期的最大电子能量。结果表明，能量标度与激光脉冲在预先形成的引导通道中传播的全尺度准三维粒子模拟结果一致，并且可直接用于优化近期激光装置中的DLA。针对与当前及近期激光技术相匹配的广泛等离子体密度范围，提出了通过匹配激光聚焦来优化DLA的策略。对于强度I∼10²¹W/cm²的激光，可获得超过10 GeV的电子能量。