Electron acceleration driven by laser wakefield using a laser pulse with circular polarization is studied to generate better-quality electron bunches. In order to inject electrons into the accelerating phase of the plasma wave, a density transition shaped bump is employed. Using particle-in-cell simulations, we demonstrate the influence of laser polarization on the quality of electron bunch. The simulation results (using experimentally achievable parameters) show that the electron bunch with higher peak-energy, narrow energy-spread, and low emittance can be obtained by using a laser pulse with circular polarization as compared to the usually employed linear polarization in a mm-scale length plasma. The results show the improved quality of the electron bunch generated from laser wakefield accelerations. The predicted electron bunch quality may be crucial in developing plasma-based electromagnetic radiation sources.

研究了使用圆偏振激光脉冲由激光尾场驱动的电子加速，以产生质量更好的电子束。为了将电子注入等离子体波的加速阶段，采用了密度过渡形状的凸块。使用细胞内粒子模拟，我们证明了激光偏振对电子束质量的影响。模拟结果（使用实验可实现的参数）表明，与通常采用的线偏振相比，使用圆偏振激光脉冲可以获得峰值能量更高、能量扩展窄、发射率低的电子束。 -尺度长度等离子体。结果表明，激光尾流场加速产生的电子束质量得到改善。