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研究了激光辐射压驱动的两级质子加速的相关问题。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电子层-离子层组成的双层结构。在激光的不断推进下，双层结构在背景等离子体里以一定速度传播，可以看成运动在背景等离子体中的电场。这样，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。通过二维 PIC 模拟方法和理论分析研究了质子加速的相关问题。研究结果表明，被加速质子的最大能量达到20 GeV。“,”Two-stage proton acceleration scheme by laser radiation pressure is investigated.When an ul-tra-intense laser interacts with a solid foil with backside underdense plasma,the laser ponderomotive force pu-shes the electrons in the foil forward and an electron-ion double layer is produced.As the laser continuously pu-shes the double layer into the backside plasma,the double layer acts like an intense moving electric field propa-gating through the underdense plasma with an almost steady speed.The protons at the backside plasma can be reflected and trapped by this moving field and be accelerated to high energies.The proposed scheme is studied by both two-dimensional particle-in-cell simulation and theoretical analysis.The proton energy spectrum shows a good profile with maximum energy above 20 GeV even after a long time.Proton acceleration with this scheme is more effective than that by the simple radiation pressure acceleration.The simulation results agree well with that of the theoretical analysis.