Sm valence states in thin Sm/graphene films supported on Ru(0001)

Samarium layers in the monolayer coverage regime were deposited on a graphene layer that was grown on a Ru(0001) substrate and subsequently investigated by photoelectron spectroscopy and low energy electron diffraction. Both divalent and trivalent Sm atoms were observed in these thin films and the fraction of divalent Sm was found to depend on the coverage in the near monolayer coverage regime. Up to a maximum of 65% divalent Sm atoms were observed for sub monolayer coverage of Sm. The Sm atoms were found to migrate to the Ru interface upon annealing above 300 K.

Automated summary

Samarium layers were deposited on graphene grown on a Ru(0001) substrate and investigated using photoelectron spectroscopy and low energy electron diffraction. Both divalent and trivalent Sm atoms were observed in these thin films, with the fraction of divalent Sm depending on the coverage in the near monolayer regime. Up to 65% divalent Sm atoms were observed for sub monolayer coverage. Upon annealing above 300 K, Sm atoms were found to migrate to the Ru interface.