Spectroscopic and DFT studies of graphene intercalation systems on metals

Highlights: • Different materials, metals and non-metals, can be intercalated in graphene on metals. • Intercalation leads to the drastic changes of the graphene properties. • ARPES, STS, and DFT are used to study the electronic structure. - Abstract: Intercalation of different species under graphene on metals is an effective way to tailor electronic properties of these systems. Here we present the successful intercalation of metallic (Cu) and gaseous (oxygen) specimens underneath graphene on Ir(111) and Ru(0001), respectively, that allows to change the charge state of graphene as well as to modify drastically its electronic structure in the vicinity of the Fermi level. We employ ARPES and STS spectroscopic methods in combination with state-of-the-art DFT calculations in order to illustrate how the energy dispersion of graphene-derived states can be studied in the macro- and nm-scale experiments.