论文标题
偶极 - 弗孔式自动离子化共振在非谐振的单色两光子单电离N $ _2 $中的作用
The role of dipole-forbidden autoionizing resonances in non-resonant one-color two-photon single ionization of N$_2$
论文作者
论文摘要
我们提出了一项实验和理论能量和角度分辨的研究，该研究对中性n $ _2 $分子的非共振单色两光子单价电离的光离子动力学。使用通过高谐波产生和3-D动量成像光谱仪产生的9.3 EV光子，我们检测到来自一层两光子电离产生的光电子和离子。 Photoionization of N$_2$ populates the X $^2Σ^+_g$, A $^2Π_u$, and B $^2Σ^+_u$ ionic states of N$_2^+$, where the photoelectron angular distributions associated with the X $^2Σ^+_g$ and A $^2Π_u$ states both vary with changes in photoelectron kinetic energy of only a few hundred meV.我们将光电子角分布的快速演变归因于属于霍普菲尔德系列的一系列不同对称性的偶极式自动离子谐振的激发和衰变，并与直接的两光子单电离竞争。
We present an experimental and theoretical energy- and angle-resolved study on the photoionization dynamics of non-resonant one-color two-photon single valence ionization of neutral N$_2$ molecules. Using 9.3 eV photons produced via high harmonic generation and a 3-D momentum imaging spectrometer, we detect the photoelectrons and ions produced from one-color two-photon ionization in coincidence. Photoionization of N$_2$ populates the X $^2Σ^+_g$, A $^2Π_u$, and B $^2Σ^+_u$ ionic states of N$_2^+$, where the photoelectron angular distributions associated with the X $^2Σ^+_g$ and A $^2Π_u$ states both vary with changes in photoelectron kinetic energy of only a few hundred meV. We attribute the rapid evolution in the photoelectron angular distributions to the excitation and decay of dipole-forbidden autoionizing resonances that belong to series of different symmetries, all of which are members of the Hopfield series, and compete with the direct two-photon single ionization.
