Bello Roger Y, Martín Fernando, Palacios Alicia
Lawrence Berkeley National Laboratory, Chemical Sciences, Berkeley, California 94720, USA.
Faraday Discuss. 2021 May 1;228:378-393. doi: 10.1039/d0fd00114g. Epub 2021 Feb 10.
We investigate how attosecond XUV pump/IR probe schemes can be used to exert control on the ionization dynamics of the hydrogen molecule. The aim is to play with all available experimental parameters in the problem, namely the XUV pump-IR probe delay, the energy and emission direction of the produced photo-ions, as well as combinations of them, to uncover control strategies that can lead to preferential electron ejection directions. We do so by accurately solving the time-dependent Schrödinger equation, with inclusion of both electronic and nuclear motions, as well as the coupling between them. We show that both the IR pulse and the nuclear motion can be used to break the molecular inversion symmetry, thus leading to asymmetric molecular-frame photoelectron angular distributions. The preferential electron emission direction can thus be tuned by varying the pump-probe delay, by choosing specific ranges of proton kinetic energies, or both. We expect that similar control strategies could be used in more complex molecules containing light nuclei.
我们研究了阿秒极紫外光泵浦/红外光探测方案如何用于控制氢分子的电离动力学。目的是对该问题中所有可用的实验参数进行调整,即极紫外光泵浦 - 红外光探测延迟、产生的光离子的能量和发射方向,以及它们的组合,以找出能够导致优先电子出射方向的控制策略。我们通过精确求解含时薛定谔方程来实现这一点,该方程同时包含电子和核运动以及它们之间的耦合。我们表明,红外脉冲和核运动都可用于打破分子的反演对称性,从而导致不对称的分子坐标系光电子角分布。因此,可以通过改变泵浦 - 探测延迟、选择质子动能的特定范围或两者同时进行来调整优先电子发射方向。我们预计类似的控制策略可用于含有轻核的更复杂分子。