Strong dichroism in the Dy 3d→4fx-ray absorption at Dy/Si(111) interfaces

Abstract
We report experimental evidence for strong 3d→4f x-ray-absorption dichroism in rare-earth ions on a nonmagnetic substrate: Dy on Si(111)7×7. The results are discussed by evaluating the role of the crystal-field splitting of the ground state as an alternative to the Zeeman splitting underlying the magnetic x-ray dichroism theory.