Magnetism at the surface of transition-metal alloys

Abstract

We study magnetic properties of transition-metal atoms at the surface of transition-metal alloys. Using two simple models for the local environment dependence of the magnetic moment of transition-metal atoms in transition-metal alloys, we determine the magnetic moments in the first few atomic layers parallel to the surface for various alloy compositions. Results are presented for Ni in Cu-Ni alloys. Results for different surface directions are given. Segregation and short-range order are taken into account. One finds that the magnetic properties at the surface of the alloys are strongly affected by surface segregation. Furthermore, in view of our results one expects changes in the magnetic behavior of transition-metal alloys due to chemisorption. We expect that surface studies are a reasonable tool to study the dependence of magnetic moments on local atomic environment.