Adsorption of Cs on InAs(1 1 1) surfaces

Caesiated InAs(1 1 1)B (1 1) and InAs(1 1 1)A (2 2) surfaces have been studied by photoelectron spectroscopy. On the InAs(1 1 1)B a new (H3 H3)R308 reconstruction was observed. During Cs evaporation remarkably small changes are observed in the lone pair states, and no sign of an accumulation layer at the surface can be observed. Instead, the additional charge provided by Cs is rapidly transported towards the bulk. On the InAs(1 1 1)A cesium behaves as a typical electropositive alkali metal donator that enhances the already existing accumulation layer.