CESIUM ADSORPTION ON GaAs(OOl) SURFACE: ADSORBATES GEOMETRY AND Sb INFLUENCE

摘要

Ab-initio full-potential linearized iiugmented-plane-wave (FLAPW) method is applied for calculations of the electronic structure of ideal GaAs(OOl) surface and Sb-covered GaAs (001) surface. The change of local densities of states in the surface and subsurface layers upon Cs adsorption on Sb-covered GaAs (001) surface is analyzed for several adsorbates sites. The role of oxygen coadsorption on GaAs(OOl) surface during cesium adsorption is also investigated. Among considered adsorption sites the T3 site (Cs is on an atom belonging to third atomic layer) is found to have the largest adsorption energy. The formation of activation layer and its electronic structure is discussed.