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arXiv · 1507.06975

Time-resolved spectroscopy at surfaces and adsorbate dynamics: insights from a model-system approach

Emil Boström·Anders Mikkelsen·Claudio Verdozzi
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Abstract

We introduce a model description of femtosecond laser induced desorption at surfaces. The substrate part of the system is taken into account as a (possibly semi-infinite) linear chain. Here, being especially interested in the early stages of dissociation, we consider a finite-size implementation of the model (i.e., a finite substrate), for which an exact numerical solution is possible. By time-evolving the many-body wave function, and also using results from a time-dependent density functional theory description for electron-nuclear systems, we analyze the competition between several surface-response mechanisms and electronic correlations in the transient and longer time dynamics under the influence of dipole-coupled fields. Our model allows us to explore how coherent multiple-pulse protocols can impact desorption in a variety of prototypical experiments.

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Emil Boström, Anders Mikkelsen, Claudio Verdozzi. 2016-05-23. Time-resolved spectroscopy at surfaces and adsorbate dynamics: insights from a model-system approach. https://doi.org/10.1103/physrevb.93.195416

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