Sangiogo Gil Eduarda, Lauvergnat David, Agostini Federica
CNRS, Institut de Chimie Physique UMR8000, Université Paris-Saclay, 91405 Orsay, France.
Institute of Theoretical Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria.
J Chem Phys. 2024 Aug 28;161(8). doi: 10.1063/5.0224779.
We employ the exact-factorization formalism to study the coupled dynamics of photons, electrons, and nuclei at the quantum mechanical level, proposing illustrative examples of model situations of nonadiabatic dynamics and spontaneous emission of electron-nuclear systems in the regime of strong light-matter coupling. We make a particular choice of factorization for such a multi-component system, where the full wavefunction is factored as a conditional electronic amplitude and a marginal photon-nuclear amplitude. Then, we apply the coupled-trajectory mixed quantum-classical (CTMQC) algorithm to perform trajectory-based simulations, by treating photonic and nuclear degrees of freedom on equal footing in terms of classical-like trajectories. The analysis of the time-dependent potentials of the theory along with the assessment of the performance of CTMQC allows us to point out some limitations of the current approximations used in CTMQC. Meanwhile, comparing CTMQC with other trajectory-based algorithms, namely multi-trajectory Ehrenfest and Tully surface hopping, demonstrates the better quality of CTMQC predictions.
我们采用精确因式分解形式体系，在量子力学层面研究光子、电子和原子核的耦合动力学，给出强光 - 物质耦合 regime 下电子 - 原子核系统非绝热动力学和自发辐射模型情况的示例。对于这样一个多组分系统，我们进行了特定的因式分解选择，其中全波函数被分解为条件电子振幅和边缘光子 - 原子核振幅。然后，我们应用耦合轨迹混合量子 - 经典（CTMQC）算法进行基于轨迹的模拟，通过在类经典轨迹方面平等对待光子和原子核自由度。对该理论随时间变化的势的分析以及对 CTMQC 性能的评估使我们能够指出 CTMQC 中当前使用的近似方法的一些局限性。同时，将 CTMQC 与其他基于轨迹的算法（即多轨迹埃伦费斯特算法和塔利表面跳跃算法）进行比较，证明了 CTMQC 预测的更好质量。
