Electronic structures and atomic surface diffusion in Cr/Fe(001) and Fe/Cr(001) systems: First-principles study

Abstract

There is currently much interest in thin-film layered systems and considerable attention has been given Fe/Cr(001) systems were quantitatively investigated in this study. Cr adatoms on the Fe(001) surface and Fe adatoms on the Cr(001) surface favored hollow sites as their adsorption site. The adsorption energies were 4.25 and 3.22 eV for each system and the surface diffusion energy barriers were calculated to be 0.99eV for Cr/Fe(001) and 1.74eV for Fe/Cr(001). Cr adatoms showed a strong antiferromagnetic phase on the Fe substrate with their spins aligned in the opposite direction to the magnetic moment of the Fe substrate, while the magnetization of ferromagnetic Fe atoms was weakened with adsorption onto the Cr substrate. During the surface diffusion process, energy states of 3d electrons in the adatom shifted toward higher levels, which corresponds to overcoming the energy barrier in both systems.