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arXiv · 1003.0790

Phonon lineshapes in atom-surface scattering

R. Martinez-Casado·A. S. Sanz·S. Miret-Artes
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Abstract

Phonon lineshapes in atom-surface scattering are obtained from a simple stochastic model based on the so-called Caldeira-Leggett Hamiltonian. In this single-bath model, the excited phonon resulting from a creation or annihilation event is coupled to a thermal bath consisting of an infinite number of harmonic oscillators, namely the bath phonons. The diagonalization of the corresponding Hamiltonian leads to a renormalization of the phonon frequencies in terms of the phonon friction or damping coefficient. Moreover, when there are adsorbates on the surface, this single-bath model can be extended to a two-bath model accounting for the effect induced by the adsorbates on the phonon lineshapes as well as their corresponding lineshapes.

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R. Martinez-Casado, A. S. Sanz, S. Miret-Artes. 2010-07-24. Phonon lineshapes in atom-surface scattering. https://doi.org/10.1088/0953-8984%2F22%2F30%2F304017

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