Spin reorientation transition of ultrathin body-centered cubic Au/Ni(001)film

Abstract

The thickness dependent magnetic properties of artificially prepared ultrathin body-centered cubic Ni films have been explored using the all electron full potential linearized augmented plane wave (FLAPW) method. Here, we have considered two types of BCC Ni(001) films : (i) pure BCC Ni(001) and (ii)Au capped BCC Ni(001) in the range from 1 monolayer (ML) to 5ML of Au capping coverage. The average magnetic moments of pure BCC Ni(001)is about 0.63 and a typical surface enhancement is found with magnetic moment of 0.78.. In the presence of Au capping layer, the magnetic moment if interface Ni is strongly suppressed to approximately 0.5 and this cause the reduction of average magnetic moment. Nevertheless, the Au adlayer has no meaningful induced magnetic moment. The BCC pure Ni(001) films have always in-plane magnetization up to 11 ML, but very interestingly the Au/Ni(001) shows thickness dependent spin reorientation transition(SRT) from in-plane to perpendicular to the film surface according to the Au coverage. However, the thickness dependent SRT shows very irregular behaviors. In addition, the calculated X-ray absorption spectroscopy(XAS) and X-ray magnetic circular dichroism (XMCD) have been presented.