First-principles studies of the magnetic properties of hcp Cr in Cr/Cu(111) and Cr/Ru(0001) superlattices

Latest first-principles density functional theoretical calculations using the generalized gradient approximation and highly accurate all-eleectron full-potential linearized augmented plane wave method, show that bulk hcp Cr would be a paramagnet and that no ferromagnetic state could be stabilized over a wide range of volume [1]. To understand the recent observation of the weakly ferromagnetic state of Cr in hcp Cr/Ru (0001) superlattices [2], the same theoretical calculations have been carried out for the hcp Cr-3/Ru-7 (0001) and hcp Cr-3/fcc Cu-6 (111) superlattices. The Cr/Ru superlattice is found to be ferromagnetic with a small magnetic moment of similar to0.31 muB/Cr while in contrast, Cr/Cu superlattice is found to be nonmagnetic.