Theoretical study of the magnetic anisotropy of Ni films on Cu(001)

The anisotropy properties of Ni films on Cu(001) are quite unusual compared to other systems: The magnetization direction of Ni is in-plane for a coverage smaller than a critical thickness of 7 monolayers and out-of-plane for a coverage larger than 7 monolayers. As a first step in the study of this unusual behaviour, we report results of ab-initio calculations of the magnetic order of Ni films on a Cu(001) substrate. The magnetic moments are computed by means of the real-space Tight-Binding LMTO method allowing non-collinear magnetic moments and including spin-orbit coupling to account for magnetic anisotropy effects. As the number of Ni layers is increased, we discuss the stability of the system with a magnetization in-plane or out-of-plane.