Structure and magnetism of FCC-Fe films on Cu(100)

The atomic and magnetic structure of FCC-Fe layers on a Cu(100) substrate is investigated by ab initio calculations as a function of the thickness of the film. Fe films with a thickness varying between 1 and 3ML stabilize a ferromagnetic (FM) ground state. For thicker films with an even number of Fe layers (4, 6 and 8ML) a bilayer AF magnetic structure develops, while for an odd number of Fe layers (5, 7 and 9ML) various spin structures coexist. The magnetic properties of Fe thin layers are compared to those of bulk FCC-Fe biaxially strained to the lattice constant of the Cu substrate and the dependence of magnetic energies in the form of the exchange-correlation functional is discussed.