We theoretically investigated the ionization dynamics of a hydrogen atom in circular excited states irradiated by the circularly polarized laser pulses by solving the time-dependent $\mathrm{Schr}\ddot{\mathrm{o}}\mathrm{dinger}$ equation. We calculated the ionization yields of the two excited states which are corotating and counter-rotating with respect to the laser fields as a function of the laser frequency. For the corotating excited state, our results show an obvious ionization suppression when the laser frequency is beyond the one-photon ionization threshold, and it is followed by a strong ionization enhancement when the laser frequency further increases. These ionization suppressions and enhancements are absent for the counter-rotating excited state. By tracing the ionization process, we found that resonance between the initial state and a lower-energy state occurs at the frequency of the ionization enhancement. Ionization from this lower-energy state is responsible for this ionization enhancement. At the frequency of ionization suppression, Rabi oscillation between the initial and the lower-energy state occurs, which prevents further ionization and thus suppresses the final ionization yield.

中文翻译：

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强激光场中氢原子圆形态的共振诱导电离增强和抑制

我们从理论上研究了圆偏振激光脉冲辐照的圆形激发态氢原子的电离动力学，解决了时间相关的问题。 $\mathrm{施尔}\ddot{\mathrm{○}}\mathrm{丁格}$方程。我们计算了相对于激光场同向旋转和反向旋转的两个激发态的电离产率，作为激光频率的函数。对于共转激发态，当激光频率超过单光子电离阈值时，我们的结果显示出明显的电离抑制，当激光频率进一步增加时，随之而来的是强烈的电离增强。对于反向旋转的激发态，不存在这些电离抑制和增强。通过追踪电离过程，我们发现初始态和低能态之间的共振发生在电离增强的频率处。这种低能量状态的电离是造成这种电离增强的原因。在电离抑制频率下，