Interlayer exchange coupling of thin equiatomic magnetic FeMn films through Cu spacer

The magnetic map of thin FeMn film deposited on Cu surfaces is determined within ab initio density functional approach. Those films made of ordered equiatomic alloys present various type of magnetization depending drastically on their thickness. Interlayer exchange coupling through the Cu spacer depends on two quantities which are the number of atomic layers in the magnetic film as well as the thickness of the Cu spacer. The results obtained show evidence of the interlayer exchange interaction in antiferromagnetic/nonmagnetic/antiferromagnetic system which could be attributed to the confinement of the electronic states in the nonmagnetic spacer through the presence of scattering potentials and the quantum mechanical exchange interaction similarly to that found classically in the ferromagnetic/nonmagnetic/ferromagnetic trilayers.