Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA.
Phys Rev Lett. 2012 Jan 20;108(3):035001. doi: 10.1103/PhysRevLett.108.035001. Epub 2012 Jan 17.
Beam-driven plasma wakefield acceleration using low-ionization-threshold gas such as Li is combined with laser-controlled electron injection via ionization of high-ionization-threshold gas such as He. The He electrons are released with low transverse momentum in the focus of the copropagating, nonrelativistic-intensity laser pulse directly inside the accelerating or focusing phase of the Li blowout. This concept paves the way for the generation of sub-μm-size, ultralow-emittance, highly tunable electron bunches, thus enabling a flexible new class of an advanced free electron laser capable high-field accelerator.
使用低离化阈值气体（如 Li）的束流驱动等离子体尾波场加速与通过高离化阈值气体（如 He）的激光控制电子注入相结合。He 电子在共线传播、非相对论强度激光脉冲的焦点处以低横向动量释放，直接位于 Li 吹出的加速或聚焦阶段内。该概念为产生亚微米尺寸、超低发射度、高度可调谐的电子束开辟了道路，从而实现了一种新型灵活的先进自由电子激光，其能够在强场加速器中运行。
