Dynamics of a frustrated rare gas monolayer adsorbed on a corrugated substrate: resonance and hybridization of the dispersion curves of Ar on MgO(100)

Abstract

Abstract The coupled dynamics of a partially commensurate monolayer with several adsorption sites on a vibrating corrugated substrate has been determined using Green function formalism. The approach is well-adapted to physisorption mechanisms. To evaluate the static properties, both the layer and the substrate are described in terms of discrete atoms whereas the substrate dynamics is considered to be that of an elastic continuum coupled to the discrete monolayer. Numerical evaluation has been performed for the 3 × 2 Ar layer on the square substrate MgO(100). Resonances and avoided crossings of the dispersion curves of the total system are studied in that case. It is shown that hybridization processes between surface acoustic branches of the substrate and the twelve dispersion curves of the monolayer are highly selective depending on the nature (quasi-acoustical, transverse or perpendicular quasi-optical) of the branches.