Electronic and Magnetic Properties of The Graphene/RE/Ni(111) (RE: La, Yb) Intercalation-Like Interfaces: A DFT Analysis

The effect of the rare-earth (RE) metals (La and Yb) intercalation on the electronic and magnetic properties of the graphene/Ni(111) interface is studied using state-of-the-art density functional theory calculations. In both systems, the intercalation of RE leads to the dramatic decrease of the magnetic moments of the Ni-interface atoms and to the negligible moments of C-atoms in a graphene layer, compared to the parent graphene/Ni(111) system. At the same time, the significant n-doping of graphene together with a band-gap opening is observed in both cases of the RE intercalation with a position of the graphene Dirac point reaching E-D - E-F approximate to -1.53 eV. Also the large density of states is found in the vicinity of the Fermi level (E-F) along the M - K direction for the graphene-derived pi states which can be attributed to the joint effect of the intercalated RE and interface Ni atoms. These factors - increased density of states at E-F and absence of magnetism of C-atoms in a graphene layer - indicate the possibility of the observation of the superconductive state in graphene in the considered RE-based systems, which is important for the understanding of these and other electronics effects in the graphene-based systems.