Photoemission, from core levels and valence band, and low-energy electron diffraction (LEED) have been employed to investigate the electronic and structural properties of novel graphene-ferromagnetic (G-FM) systems,obtained by intercalation of one mono-layer (1ML) and several layers (4ML) of Co on G grown on Ir(111). Upon intercalation of 1ML of Co, the Co lattice is resized to match the Ir-Ir lattice parameter, resulting in a mismatched G/Co/Ir(111) system. The intercalation of further Co layers leads to a relaxation of the Co lattice and a progressive formation of a commensurate G layer lying on top. We show the C 1s line shape and the band structure of G in the two artificial phases, mismatched and commensurate G/Co, through a comparison with the electronic structure of G grown directly on a Co thick film. Our results show that while the G valence band mainly reflects the hybridization with the d states of Co, regardless of the structural phase, the C 1s line shape is very sensitive to the rumpling of the G layer and the coordination of carbon atoms with the underlying Co. Even in the commensurate (1x1) G/Co phase, where graphene is in register with the Co film, from the angular dependence of the C 1s core level we infer the presence of a double component, due to in-equivalent adsorption sites of carbon sub-lattices.
@article{arxiv.2602.19955,
title = {Electronic structure of Graphene/Co interfaces},
author = {Daniela Pacilé and Simone Lisi and Iolanda Di Bernardo and M. Papagno and L. Ferrari and Michele Pisarra and Marco Caputo and S. K. Mahatha and P. M. Sheverdyaeva and P. Moras and P. Lacovig and Silvano Lizzit and Alessandro Baraldi and Maria Grazia Betti and Carlo Carbone},
journal= {arXiv preprint arXiv:2602.19955},
year = {2026}
}