Line Shape Broadening in Surface Diffusion of Interacting Adsorbates with Quasielastic He Atom Scattering

Abstract

The experimental line shape broadening observed in adsorbate diffusion on metal surfaces with increasing coverage is usually related to the nature of the adsorbate-adsorbate interaction. Here we show that this broadening can also be understood in terms of a fully stochastic model just considering two noise sources: (i) a Gaussian white noise accounting for the surface friction, and (ii) a shot noise replacing the physical adsorbate-adsorbate interaction potential. Furthermore, contrary to what could be expected, for relatively weak adsorbate-substrate interactions the opposite effect is predicted: line shapes get narrower with increasing coverage.

4 pages, 2 figures (slightly revised version)

Cited by in corpus (3)

• Quasielastic He atom scattering from surfaces: A stochastic description of the dynamics of interacting adsorbates
• Stochastic theory of lineshape broadening in quasielastic He atom scattering with interacting adsorbates
• Quantum Markovian activated surface diffusion of interacting adsorbates