Protecting Au-stabilized vicinal Si surfaces from degradation: Graphene on the Si(5Â 5Â 3)-Au surface

We propose an efficient method of protecting the Au-induced stepped Si(5 5 3) surface from degradation when exposed to the environment. This applies to both the atomic and electronic structures, and is achieved by covering the surface with graphene. Using density functional theory we show that graphene deposited on the Si(5 5 3)-Au surface extremely weakly interacts with it, leaving its structural and electronic properties unaltered. In particular, the π-electrons of graphene are completely decoupled from electrons of the surface Au chains. At the same time, the graphene-covered Si(5 5 3)-Au surface is more resistant to the adsorption of foreign atoms, which is very promising in view of technological applications of the Au-stabilized vicinal Si surfaces. The proposed idea could be generalized to other vicinal Si surfaces.