We theoretically investigate the ionization process of the interaction between a strong circular polarized laser pulse and an atom, whose initial state has different orbital angular momenta. When the rotation direction of the laser vector field is opposite to that of the bound state, the ionization probability is significantly higher than the co-rotating case, in which the laser vector field is in the rotational direction of the bound electron. Especially, with the increase of the incident laser’s wavelength, the ionization probability is enhanced for the co-rotating case, and it is on the contrary in the counter-rotating case. By analyzing electronic trajectories in both cases, it is demonstrated that, the difference of variations of the ionization probability with the laser’s wavelength can be attributed to that of durations from the electron passing through the exit of the over-the-barrier potential, which is formed by the atom potential and the laser field.

我们从理论上研究了强圆偏振激光脉冲与原子之间相互作用的电离过程，该原子的初始状态具有不同的轨道角动量。当激光矢量场的旋转方向与束缚态的旋转方向相反时，电离概率明显高于同向旋转的情况，在这种情况下，激光矢量场沿束缚电子的旋转方向。特别是，随着入射激光波长的增加，在同向旋转的情况下，电离概率增加，而在反向旋转的情况下相反。通过分析两种情况下的电子轨迹，可以证明，