Comparative study of photoelectron momentum distributions from Kr and CO2 near a backward rescattering caustic by carrier-envelope-phase mapping
Comparative study of photoelectron momentum distributions from Kr and CO2 near a backward rescattering caustic by carrier-envelope-phase mapping
复制标题
通过载流子包络相位映射比较研究来自向后重散射焦散附近的 Kr 和 CO2 的光电子动量分布
DOI：
10.1103/physreva.107.033101
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
and J. Itatani
中科院分区：
文献类型：
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作者：
T. Mizuno;T. Yang;T. Kurihara;N. Ishii;T. Kanai;O. I. Tolstikhin;T. Morishita;and J. Itatani
本文研究了线偏振亚双周期强红外场作用下Kr原子和随机取向分子的光电子动量分布（PEMD）随载流子包络相位（CEP）的变化。绝热理论预测，在固定的激光参数（强度，脉冲持续时间，和CEP），PEMD的目标具有相等的电离势考虑跨越后向再散射焦散具有相同的形状，只有它们的绝对值取决于目标。我们选择Kr和具有几乎相同的电离势（约为1.5V）的靶来探索PEMD的这种行为。我们发现，测量的PEMD Kr和有截止结构，这是与焦散线，具有相同的衰减配置文件。我们还发现，CEP依赖PEMD的截止附近表现出目标的依赖性，反映了弹性再散射和隧道电离率的微分截面（DCS）的差异。此外，我们根据绝热理论，从不同CEP下截止点附近的PEMD中提取了DCS。提取的DCS同意通过使用单活性电子（SAE）散射模型，其中包括所有的多散射过程，取向平均计算。相反，独立原子模型，它只考虑单散射过程，不能再现提取的DCS在低散射动量。这一发现表明，在1.5-2.5 a. u的动量范围内，多次散射是不可忽略的。提取的DCS也显示出分配给O-O和C-O的多中心散射的干涉特征。这些结果证实，电子干扰的签名后保留取向平均，表明组成原子的核间距可以检索从CEP依赖的PEMD随机取向的分子使用SAE模型。
We study carrier-envelope-phase- (CEP-) dependent photoelectron momentum distributions (PEMDs) of Kr atoms and randomly orientedmolecules exposed to sub-two-cycle intense infrared fields with linear polarization. The adiabatic theory predicts that, at fixed laser parameters (intensity, pulse duration, and CEP), the PEMDs for targets with equal ionization potentials considered across a backward rescattering caustic have identical shapes and only their absolute values depend on the target. We choose Kr andas targets with almost identical ionization potentials (approximatelyeV) to explore this behavior of PEMDs. We find that the measured PEMDs for Kr andhave cutoff structures, which are associated with the caustics, with identical decaying profiles. We also reveal that CEP-dependent PEMDs around the cutoff exhibit target dependence, reflecting the differences in the differential cross sections (DCSs) of elastic rescattering and tunneling ionization rates. Furthermore, we extract the DCSs from the measured PEMDs around the cutoffs at different CEPs based on the adiabatic theory. The extracted DCSs agree with ones calculated by using the single-active-electron (SAE) scattering model, which includes all multiple-scattering processes, with orientation averaging for. In contrast, the independent-atom model, which only considers single-scattering processes, cannot reproduce the extracted DCSs ofat low scattering momenta. This finding indicates that multiple scattering is not negligible in the momentum range of 1.5–2.5 a.u. The extracted DCSs also show interference features assigned to multicenter scattering of O-O and C-O. These results confirm that the signature of electron interference is retained after orientation averaging, indicating that the internuclear distances of the constituent atoms can be retrieved from the CEP-dependent PEMDs for randomly oriented molecules using the SAE model.