Papers by Keyword: Ultrathin Magnetic Films

Abstract: Theoretical description of multilayer ferromagnetic films from Fe, Co, and Ni transition metals on a nonmagnetic metal substrate is considered by the spin-density functional method. The energy and magnetic characteristics of multilayer films are calculated for surface systems Fe (110)/W(110), Fe (110)/Ag (111), Ni (111)/Cu (111), and Сo (111)/Cu (111) in dependence on film thickness for different temperatures, based on critical behavior characteristics of films.

Abstract: Theoretical description of ultrathin ferromagnetic Fe and Ni alloy film adsorption on a nonmagnetic metal substrate is considered by the spin-density functional method. The conditions for the formation of ultrathin ferromagnetic films stable with respect to island adsorption with a change in the coverage parameter θ and Fe content concentration x are revealed. The equilibrium vacuum gap D_min and the equilibrium film thickness h_min are determined from the minimum of the total interfacial energy. The energy and magnetic characteristics of Fe_xNi_1-x films on close-packed W and Cu surfaces are calculated in dependence on concentration x for different temperatures.

Abstract: At present time, a large number of experimental works have been devoted to the study of magnetic ordering in Fe, Co, and Ni ultrathin films [. The investigation of a nature of magnetism in these structures has a large fundamental interest through an observable dimensionality crossover of magnetic characteristics from three dimensional values for films with thickness d 10 nm to two dimensional values for films with thickness d 1-2 nm. It has been established that the long-range ferromagnetic order arises in films at some effective film thickness. However, the nature and regularities of this phenomenon remain not quite clear. In our paper [ it was developed in terms of the spin-density functional theory the description of influence of the temperature and ferromagnetic ordering on the adsorption of Fe, Co, and Ni transition metal ions on a nonmagnetic substrate with the formation of a submonolayer films. For case of nonactivated adsorption the conditions for the formation of magnetic monoatomic films stable with respect to island adsorption with a change in the coverage parameter θ are revealed. It was demonstrated that the inclusion of the ferromagnetic ordering substantially affects the adsorption energy and leads to its considerable increase.

Abstract: The thermal-driven evolution of stripe domain structures in ultrathin magnetic films is analyzed with regard to temperature dependencies of the film magnetic parameters. In the vicinity of the Curie temperature or points of the spin reorientation the equilibrium stripe domain period was found to exponentially decrease with increasing temperature. It is shown that the temperature dependence of the characteristic length is the key parameter controlling the domain period changes. Irreversible and reversible changes of the domain period as well as the so-called inverse domain melting are discussed.