标题： 高强度空间非均匀场中高于阈值电离的量子轨道分析 显示英文标题

标题： Quantum-orbit analysis of above threshold ionization by intense spatially inhomogeneous field

摘要： 我们通过考虑空间非均匀的单色激光场，在强场近似（SFA）中对原子中的高于阈值电离（ATI）进行了详细分析。 由共振等离子体引起的局部增强场是这种非均匀场的一个例子。 我们研究了单独的量子轨道对光电子谱和角度电子动量分布的贡献。 我们证明，与均匀场相比，量子轨道在空间非均匀场中表现出非常不同的行为。 在非均匀场的情况下，尽管场是单色的，相邻周期的电离和再散射时间有所不同。 实际上，来自一个周期的贡献可能导致较低的截止，而另一个周期可能产生较高的截止。 在我们的模型中，我们表明ATI截止随着非均匀性强度的变化远超过半经典截止。 此外，角动量分布与均匀情况下的特征有显著不同。 对于相邻周期，电子动量分布不具有相同的绝对动量，它们的产率也不相同。 显示英文摘要

摘要： We perform a detailed analysis of above threshold ionization (ATI) in atoms within the strong field approximation (SFA) by considering spatially inhomogeneous monochromatic laser fields. The locally enhanced field induced by resonance plasmons is an example for such inhomogeneous fields. We investigate how the individual pairs of quantum orbits contribute to the photoelectron spectra and the angular electron momentum distributions. We demonstrate that the quantum orbits have a very different behavior in the spatially inhomogeneous field when compared to the homogeneous field. In the case of inhomogeneous fields, the ionization and rescattering times differ between neighboring cycles, despite the field being monochromatic. Indeed, the contributions from one cycle may lead to a lower cutoff, while another may develop a higher cutoff. Within our model, we show that the ATI cutoff extends far beyond the semiclassical cutoff, as a function of inhomogeneity strength. Furthermore, the angular momentum distributions have very different features compared to the homogeneous case. For the neighboring cycles, the electron momentum distributions do not share the same absolute momentum, and they do not have the same yield