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Importance of Correlation Effects on Magnetic Anisotropy in Fe and Ni

Imseok Yang·Sergej Y. Savrasov·Gabriel Kotliar
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Abstract

We calculate magnetic anisotropy energy of Fe and Ni by taking into account the effects of strong electronic correlations, spin-orbit coupling, and non-collinearity 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 MAE 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.

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Imseok Yang, Sergej Y. Savrasov, Gabriel Kotliar. 2001-07-03. Importance of Correlation Effects on Magnetic Anisotropy in Fe and Ni. https://arxiv.org/abs/cond-mat/0107063

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