Enhanced ionization of hydrogen molecular ions in an intense laser field via a multiphoton resonance
Enhanced ionization of hydrogen molecular ions in an intense laser field via a multiphoton resonance
复制标题
DOI：
10.1103/physreva.81.013408
复制
发表时间：
2010-01
影响因子：
2.9
通讯作者：
Ying-Jun Jin;X. Tong;N. Toshima
中科院分区：
文献类型：
--
作者：
Ying-Jun Jin;X. Tong;N. Toshima
通过在长球面坐标系下求解时变薛定谔方程，研究了氢分子离子在480 nm强激光场中的多光子电离。在广义伪谱网格上离散空间，利用二阶分裂算子方法传播电子波函数。通过在基展开中包括和排除2psigma{sub u}态，我们证实了在最近的实验中观察到的10- ev峰[Litvinyuk et al., New J. Phys. 10, 083011(2008)]来自于分子离子通过三光子共振激发而增强的电离。将计算得到的电离率与振动密度分布进行折叠，得到了与实验测量结果较为吻合的动能释放谱。此外，利用这种增强的电离，提出了一种泵探实验来跟踪振动波包。
Multiphoton ionization of hydrogen molecular ions in a 480-nm intense laser field is investigated by solving the time-dependent Schroedinger equation numerically in prolate spheroidal coordinates. We discretize space on a generalized pseudospectral grid and propagate the electronic wave function using a second-order split-operator method. By including and excluding the 2psigma{sub u} state in the basis expansion, we confirm that the observed 10-eV peak in a recent experiment [Litvinyuk et al., New J. Phys. 10, 083011 (2008)] comes from the enhanced ionization via three-photon resonant excitation of the molecular ions. By folding the calculated ionization rates with the vibrational density distribution, the kinetic energy release spectra are obtained, which are in reasonable agreement with the experimental measurement. Furthermore, using this enhanced ionization, a pump-probe experiment is suggested to trace the vibrational wave packet.