arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2203.09820physics.chem-ph
收藏

表面非马尔可夫振动弛豫动力学

Non-Markovian Vibrational Relaxation Dynamics at Surfaces

Eric W. Fischer, Michael Werther, Foudhil Bouakline, Frank Grossmann, Peter Saalfrank

摘要:

表面吸附物的振动动力学不仅在应用表面科学中起着重要作用,而且是研究开放量子系统基本问题的模型实验室。我们采用了一个先前开发的模型,在D:Si(100)-(2 $\times$ 1)表面的D-Si-Si弯曲模式的弛豫,诱导的“浴”的多个$2000$声子模式[U。Lorenz,P. Saalfrank,Chem. Phys. { \bf 482},69(2017)],以沿着各个方向扩展先前的工作。首先,我们使用分层有效模式(HEM)模型[E.W. Fischer,F. Bouakline,M. Werther,P. Saalfrank,J. Chem. Phys. { \bf 153},064704(2020)]通过求解高维系统浴时间依赖性薛定谔方程(TDSE)来研究比迄今所做的更高激发振动态的弛豫。在HEM方法中,(许多)真实浴模式被(少得多的)有效浴模式取代。因此,我们能够检查一个现实的表面科学问题的振动弛豫寿命的标度律。其次,我们比较了多层多组态含时Hartree(ML-MCTDH)方法和最近发展的基于相干态的多Davydov D2 { \it analog} [N. Zhou,Z.作者:Huang,J. Zhu,V. Chernyak,Y. Zhao,{J. Chem. Phys.} { \bf 143},014113(2015)]。这两种方法都工作得很好,后者在所提出的上下文中具有一些计算优势。第三,我们应用开放系统的密度矩阵理论与基本上“精确”的多模式TDSE的解决方案进行比较。具体来说,我们使用一个开放系统的Liouville-冯诺依曼(LVN)方程治疗的振动-声子耦合的马尔可夫耗散Lindblad形式的量化效果超出Born-Markov近似。

英文摘要:

Vibrational dynamics of adsorbates near surfaces plays both an important role for applied surface science and as model lab for studying fundamental problems of open quantum systems. We employ a previously developed model for the relaxation of a D-Si-Si bending mode at a D:Si(100)-(2$\times$1) surface, induced by a "bath" of more than $2000$ phonon modes [U. Lorenz, P. Saalfrank, Chem. Phys. {\bf 482}, 69 (2017)], to extend previous work along various directions. First, we use a Hierarchical Effective Mode (HEM) model [E.W. Fischer, F. Bouakline, M. Werther, P. Saalfrank, J. Chem. Phys. {\bf 153}, 064704 (2020)] to study relaxation of higher excited vibrational states than hitherto done, by solving a high-dimensional system-bath time-dependent Schrödinger equation (TDSE). In the HEM approach, (many) real bath modes are replaced by (much less) effective bath modes. Accordingly, we are able to examine scaling laws for vibrational relaxation lifetimes for a realistic surface science problem. Second, we compare the performance of the multilayer multiconfigurational time-dependent Hartree (ML-MCTDH) approach with the recently developed coherent-state based multi-Davydov D2 {\it ansatz} [N. Zhou, Z. Huang, J. Zhu, V. Chernyak, Y. Zhao, {J. Chem. Phys.} {\bf 143}, 014113 (2015)]. Both approaches work well, with some computational advantages for the latter in the presented context. Third, we apply open-system density matrix theory in comparison with basically "exact" solutions of the multi-mode TDSEs. Specifically, we use an open-system Liouville-von Neumann (LvN) equation treating vibration-phonon coupling as Markovian dissipation in Lindblad form to quantify effects beyond the Born-Markov approximation.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑