AI 中文总结
本文针对双色场驱动下多个光诱导锥形交叉点的非绝热动力学，构建三通道Floquet哈密顿量，对比量子波包动力学与双模式F-FSSH方法，明确了光子能量和场强的调控作用，验证了双模式F-FSSH的适用性，深化了对相关动力学的认识。
AI 中文摘要
光诱导锥形交叉点（LICIs）为非绝热跃迁创造了外部可调的路径，可实现对分子光物理和光化学过程的主动控制。然而，双色场驱动下多个LICIs附近的动力学，以及我们近期开发的双模式Floquet最少表面跳跃（two-mode F-FSSH）方法在该场景下的适用性，仍未得到充分理解。本文针对与双色场相互作用的Na₂，构建了支持两个LICIs的最简三通道Floquet哈密顿量，表征其静态Floquet性质，并采用数值精确的量子波包动力学和双模式F-FSSH研究相关非绝热动力学。研究发现，第二个光子能量控制LICIs的相对位置，而第二个场的强度主要使第二个LICI附近的导数耦合分布发生重排并展宽。因此，电子布居转移和分子取向对这两个控制参数呈现出不同且常为非单调的响应。双模式F-FSSH可可靠捕获早期动力学的主要特征，并对瞬态后的时间平均可观测量提供半定量描述。这些发现从物理和方法层面推进了对LICI介导动力学的理解。
英文摘要
Light-induced conical intersections (LICIs) create externally tunable pathways for nonadiabatic transitions, enabling active control of molecular photophysical and photochemical processes. However, both the dynamics near multiple LICIs under bichromatic driving and the applicability of our recently developed two-mode Floquet fewest switches surface hopping (two-mode F-FSSH) method to this regime remain insufficiently understood. Here, we construct a minimal three-channel Floquet Hamiltonian supporting two LICIs for Na2 interacting with a bichromatic field. We characterize its static Floquet properties and investigate the associated nonadiabatic dynamics using numerically exact quantum wave-packet dynamics and two-mode F-FSSH. We find that the second photon energy controls the relative positions of the LICIs, whereas the second-field intensity primarily redistributes and broadens the derivative-coupling landscape around the second LICI. Consequently, electronic population transfer and molecular alignment exhibit distinct and often nonmonotonic responses to these two control parameters. Two-mode F-FSSH reliably captures the principal features of the early-time dynamics and provides a semiquantitative description of the post-transient time-averaged observables. These findings advance our understanding of LICI-mediated dynamics at both the physical and methodological levels.
