Onset of magnetic anisotropy in ion-sculpted ultrathin magnetic films

The onset of in-plane uniaxial magnetic anisotropy in ion-sculpted ultrathin Fe/Ag(001) films has been investigated. Uniaxial anisotropy already develops at ion fluences where the self-organisation of the ripple structure has not yet started. The evolution of the strength of the uniaxial anisotropy as a function of ion fluence allows to identify the step unbalance at the ion-sculpted surface as the origin of the magnetic anisotropy.