论文标题
谐振高谐波生成中的深色和明亮的自动离子态：通过1D氦模型模拟
Dark and bright autoionizing states in resonant high harmonic generation: simulation via 1D helium model
论文作者
论文摘要
我们使用一维氦模型研究了黑暗自动离子态（AIS）在光电离和高谐波（HHG）中的作用。该模型允许将时间依赖性的schrödinger方程式超出单元近似的数值整合，完全考虑到电子相关性。我们找到了包括AIS在内的几个状态的系统的水平结构以及电子密度的空间分布。研究HHG效率是与AIS共振引起的函数，我们找到了HHG增强线。这些线的形状与光电光谱中相应的Fano系不同，与氦的实验研究一致。此外，我们在基本频率接近与黑暗AIS的均衡多光子共振接近时模拟HHG。我们发现相邻奇怪的谐波的增强。可以理解这些谐波的增强线的细节，考虑到非谐振和谐振XUV的发射之间的时间延迟；此延迟由AIS寿命定义。最后，我们的模拟表明，在研究系统中，由于黑暗和明亮的AIS引起的HHG增强。
We study the role of dark and bright autoionizing states (AIS) in photoionization and high harmonic generation (HHG) using a 1D helium model. This model allows numerical integration of the time-dependent Schrödinger equation beyond the singe-electron approximation completely taking into account electronic correlation. We find the level structure of the system and the spatial distribution of the electronic density for several states including AIS. Studying the HHG efficiency as a function of the detuning from the resonances with AIS we find the HHG enhancement lines. The shapes of these lines are different from the corresponding Fano lines in the photoelectronic spectra, in agreement with the experimental studies in helium. Moreover, we simulate HHG under the conditions when the fundamental frequency is close to the even-order multiphoton resonance with the dark AIS. We find the enhanced generation of the neighbouring odd harmonics. The details of the enhancement lines for these harmonics can be understood taking into account the temporal delay between the emission of the non-resonant and resonant XUV; this delay is defined by the AIS lifetime. Finally, our simulations show that the HHG enhancement due to the dark and the bright AIS is comparable in the studied system.
