Korani Youssef, Sabzyan Hassan
Department of Chemistry, University of Isfahan, Isfahan 81746-73441, Islamic Republic of Iran.
Phys Chem Chem Phys. 2017 Nov 29;19(46):31138-31155. doi: 10.1039/c7cp06435g.
The effects of the orientation, wavelength and carrier-envelope phase of laser pulses on the spin fluctuation in HeH and LiH molecular ions in their bound electronic states, during their interactions with linearly polarized intense laser pulses, were investigated by solving numerically the time-dependent Dirac equation with the Foldy-Wouthuysen transformation. The results of this study showed that an increase in the wavelength of the laser pulse at a fixed intensity reduces the lifetime of the coherent spin states and increases the sensitivity of the spin vector to the applied laser field in both HeH and LiH species. This sensitivity also depends on the carrier-envelope phase of the laser pulse due to the asymmetry of these systems. Furthermore, the influence of spin-orbit coupling on the dynamics of the spin in the interaction of the highly charged atomic species, N, with ultra-intense laser pulses was investigated by considering different initial orbitals and spin polarizations. The results show that significantly different spin-forces are induced when an interaction starts with two parallel and perpendicular polarized spin states with respect to the direction of the laser pulse propagation. Furthermore, spin-orbit coupling affects the quantization of the spin space and results in asymmetric spin fluctuation depending on the initial spin polarization state and the electron orbital momentum, which is induced by the electric field of the laser pulse.
通过用Foldy-Wouthuysen变换数值求解含时狄拉克方程，研究了激光脉冲的取向、波长和载波包络相位在与线偏振强激光脉冲相互作用期间，对处于束缚电子态的HeH和LiH分子离子自旋涨落的影响。该研究结果表明，在固定强度下，激光脉冲波长的增加会缩短HeH和LiH两种分子中相干自旋态的寿命，并增加自旋矢量对外加激光场的敏感性。由于这些系统的不对称性，这种敏感性还取决于激光脉冲的载波包络相位。此外，通过考虑不同的初始轨道和自旋极化，研究了自旋轨道耦合对高电荷原子物种N与超强激光脉冲相互作用中自旋动力学的影响。结果表明，当相互作用从相对于激光脉冲传播方向的两个平行和垂直极化自旋态开始时，会诱导出显著不同的自旋力。此外，自旋轨道耦合会影响自旋空间的量子化，并导致取决于初始自旋极化状态和由激光脉冲电场诱导的电子轨道动量的不对称自旋涨落。
