Faisal F H M, Abdurrouf A, Miyazaki K, Miyaji G
Fakultät für Physik, Universität Bielefeld, Postfach 100131, D-33501 Bielefeld, Germany.
Phys Rev Lett. 2007 Apr 6;98(14):143001. doi: 10.1103/PhysRevLett.98.143001. Epub 2007 Apr 2.
Recent pump-probe experiments with intense femtosecond laser pulses and diatomic molecules N2 and O2, have revealed the presence of Raman-forbidden anomalous series and lines in the Fourier spectrum of HHG (high harmonic generation) signals. A theoretical analysis of the problem is made by deriving a general expression of the angle dependent HHG operator that governs the dynamic alignment signals in linear molecules, and applying them to the experiments in N2 and O2. A unified interpretation of the origin of the observed Raman-allowed and the anomalous spectral features is given. The results are also used to estimate the molecular temperature in the experiments.
最近利用高强度飞秒激光脉冲与双原子分子N₂和O₂进行的泵浦-探测实验，揭示了高次谐波产生（HHG）信号的傅里叶光谱中存在拉曼禁戒的反常谱线系列。通过推导控制线性分子中动态取向信号的与角度相关的HHG算符的一般表达式，并将其应用于N₂和O₂的实验，对该问题进行了理论分析。给出了对所观察到的拉曼允许和反常光谱特征起源的统一解释。这些结果还用于估计实验中的分子温度。
