论文标题
激光诱导的电子菲涅耳衍射和隧道中的过度障碍电离
Laser-induced electron Fresnel diffraction in the tunneling and over-barrier ionization
论文作者
论文摘要
强场电离中的光电子动量分布具有多种结构，这些结构揭示了该过程的复杂动力学。最近，我们确定了在超强度极端紫外线（XUV）激光脉冲的情况下，低能的干扰结构，并将其归因于激光诱导的电子弗塞尔德衍射。该结构由激光诱导的电子位移确定[Geng L等。 2021 Phys。修订版A 104（2）L021102]。在目前的工作中，我们发现短脉冲的隧道和过度障碍物状态中也存在菲涅尔衍射图。但是，现在，在生物XUV脉冲的情况下，激光脉冲的电场成分而不是磁场成分引起电子位移。在对我们的量子和半经典模型进行了相应的修改之后，我们发现菲涅耳衍射的相同物理机理控制着沿激光极化的低能干扰结构。这两个模型预测的结果与时间依赖性的Schrodinger方程的数值解决方案的准确结果非常吻合。
The photoelectron momentum distribution in the strong-field ionization has a variety of structures that reveal the complicated dynamics of this process. Recently, we identified a low-energy interference structure in the case of a super-intense extreme ultraviolet (XUV) laser pulse and attributed it to the laser-induced electron Fresnel diffraction. This structure is determined by the laser-induced electron displacement [Geng L et al. 2021 Phys. Rev. A 104(2) L021102]. In the present work, we find that the Fresnel diffraction picture is also present in the tunneling and over-barrier regime of ionization by short pulses. However, the electron displacement is now induced by the electric field component of the laser pulse, instead of by the magnetic field component in the case of the superintense XUV pulse. After corresponding modifications to our quantum and semiclassical models, we find the same physical mechanism of the Fresnel diffraction governs the low-energy interference structures along the laser polarization. The results predicted by the two models agree well with the accurate results from the numerical solution to the time-dependent Schrodinger equation.
