为了研究激光辐射压驱动的运动电场中加速质子的相关问题, 对强激光与等离子体相互作用过程进行了理论分析, 并采用2维粒子模拟方法, 对理论分析结果进行了数值模拟验证。结果表明, 当超短超强激光脉冲与处在背景等离子体前方的薄固体平靶相互作用时, 在固体靶后部形成一个由电子层-离子层组成的双层结构, 在激光辐射压的不断推进下, 双层结构在背景等离子体里以一定速度传播形成一个运动电场; 在背景等离子体中的质子被这个运动电场捕获并能加速到很高的能量, 质子的最大能量达到20GeV。理论分析结果与2维粒子模拟结果符合得很好。

In order to study the proton acceleration of the moving electric field driven by laser radiation pressure, the interaction process between high power laser and laser plasma was analyzed theoretically. 2-D particle-in-cell simulations was used to verify the theoretical analysis result. The results show that when the interaction between ultra-short ultra-intense laser pulse and thin solid flat target in front of the background plasma, a bilayer structure consisted by electron layer and ion layer was generated at the back of the solid target. Under the constant advancement of laser radiation pressure, the double layer structure in the background plasma spreaded at a certain speed and formed a moving electric field. Protons in background plasma were captured by this moving electric field and accelerated to a very high energy. The maximum proton energy reached 20GeV. The results of theoretical analysis are in good agreement with the simulation results of 2-D particle.