论文标题
通过时间分辨X射线光谱法，原子动力学对原子动力学的原子特异性探测
Atom-Specific Probing of Electron Dynamics in an Atomic Adsorbate by Time-Resolved X-ray Spectroscopy
论文作者
论文摘要
从启动表面化学反应的光学激光器的超快时间尺度上出现在吸附物上的电子激发仍然是一个开放的问题。在这里，我们报告了X射线吸收光谱（XAS）和X射线发射光谱（XES）的超快速时间演变的超快速性碳（c）原子，即在镍（Ni（Ni（100））表面上，碳原子（c）原子都被吸附在400 n mms in nike（ni（ni（ni（100））上））。我们观察到XAS和XE的超快（〜100 fs）变化，显示了在吸附物上形成热电子孔对分布的明显特征。接下来是几个PS时间尺度上的变化较慢，这与完整C/NI系统的热化相一致。密度功能理论频谱模拟支持此解释。
The electronic excitation occurring on adsorbates at ultrafast time scales from optical lasers that initiate surface chemical reactions is still an open question. Here, we report the ultrafast temporal evolution of X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) of a simple well known adsorbate prototype system, namely carbon (C) atoms adsorbed on a nickel (Ni(100)) surface, following intense laser optical pumping at 400 nm. We observe ultrafast (~100 fs) changes in both XAS and XES showing clear signatures of the formation of a hot electron-hole pair distribution on the adsorbate. This is followed by slower changes on a few ps time scale, shown to be consistent with thermalization of the complete C/Ni system. Density functional theory spectrum simulations support this interpretation.
