发表机构
Institute of Molecular Physical Science, ETH Zurich（苏黎世联邦理工学院分子物理科学研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出MASH-PLDM方法，结合部分线性化密度矩阵与表面跳跃，改进非绝热动力学模拟，尤其在相干性重要场景，并支持非线性光谱多时间关联函数计算。
AI 中文摘要
我们推导了映射方法用于表面跳跃（MASH）的一种部分线性化版本，为模拟分子系统中的非绝热动力学提供了一种新方法。与原始MASH形式一样，轨迹在绝热表面上运动，跳跃由Bloch球上自旋矢量的动力学决定。然而，由于新方法基于部分线性化密度矩阵（PLDM），它有两个自旋矢量，它们可能位于Bloch球的相同或不同半球。前者描述电子布居在单一绝热表面上运动，而后者描述相干性在平均表面上运动。我们表明，这种称为MASH-PLDM的新方法在多种散射问题和自旋-玻色子模型中，相比于原始MASH动力学，产生了改进的结果，特别是在相干性起重要作用的案例中。新方法的另一个优点是它可以处理多时间关联函数，例如非线性光谱所需的那些。我们通过时间分辨泵浦-探测光谱的原理验证模拟来展示这一能力。
英文摘要
We derive a partially linearized version of the mapping approach to surface hopping (MASH) that provides a new method for simulating nonadiabatic dynamics in molecular systems. As in the original MASH formalism, trajectories travel on adiabatic surfaces with hops determined by the dynamics of a spin vector on the Bloch sphere. However, because the new approach is based on the partially linearized density matrix (PLDM), it has two spin vectors, which may be in the same or different hemispheres of the Bloch sphere. The former scenario describes an electronic population moving on a single adiabatic surface, whereas the latter describes a coherence moving on the average surface. We show that this new method, called MASH-PLDM, leads to improved results over the original MASH dynamics for a variety of scattering problems and spin-boson models, especially in cases where coherences play an important role. A further benefit of the new methodology is that it can treat multi-time correlation functions such as those required for nonlinear spectroscopy. We demonstrate this capability with a proof-of-principle simulation of time-resolved pump-probe spectroscopy.
Comments53 pages, 18 figures
