Surface magnetism of 3d monolayers on a W(110) substrate probed by X-ray magnetic circular dichroism

A theoretical investigation of the X-ray magnetic circular dichroism (XMCD) and the magnetic properties of a Fe. Co and Ni monolayer on a W(1 1 0) sub strate is presented. The Ni monolayer shows very weak ferromagnetism, where as Fe- and Co-based systems show an in-plane magnetization in agreement wit h experiments. The Fe and Co spin magnetic moments are reduced from their b ulk value due to the surface relaxation and the hybridization with the d va lence electrons of W. The orbital magnetic moments are found to be larger f or the in-plane magnetization axis for all atoms. The calculated XMCD spect ra reflect the anisotropy of the orbital magnetic moments. (C) 2001 Elsevie r Science B.V. All rights reserved.