Noncollinear magnetism caused by intermixing at ferromagnetic/antiferromagnetic interfaces

Fe-Cr alloy layers on Fe 001 substrates with different atomic environments are theoretically investigated through a self-consistent real-space tight-binding method parametrized to density functional theory and without collinear restriction for the spin directions. We show that the intermixing at the Cr/Fe interface, experimentally observed at the first stages of the Cr growth on Fe, originates noncollinear magnetic arrangements within the system and even induces magnetic walls in the Fe layer with a magnetic domain close to the interface. A different behavior is shown if steps are present at the interface; i.e., noncollinear magnetism becomes more localized and the induced magnetic wall in Fe vanishes.