title: Importance of correlation effects on magnetic anisotropy in Fe and Ni.
abstract: We calculate magnetic anisotropy energy of Fe and Ni by taking into account the effects of strong electronic correlations, spin-orbit coupling, and noncollinearity of intra-atomic magnetization. The LDA+U method is used and its equivalence to dynamical mean-field theory in the static limit is emphasized. Both experimental magnitude of magnetic anisotropy energy and direction of magnetization are predicted correctly near U = 1.9 eV, J = 1.2 eV for Ni and U = 1.2 eV, J = 0.8 eV for Fe. Correlations modify the one-electron spectra which are now in better agreement with experiments.
authors.affiliation: Department of Physics and Astronomy and Center for Condensed Matter Theory, Rutgers University, Piscataway, New Jersey 08854, USA.
authors.forename: I
authors.initials: I
authors.lastname: Yang
authors.forename: S Y
authors.initials: SY
authors.lastname: Savrasov
authors.forename: G
authors.initials: G
authors.lastname: Kotliar