First-principles investigation of the very large perpendicular magnetic anisotropy at Fe | MgO and Co | MgO interfaces

Abstract
The perpendicular magnetic anisotropy (PMA) arising at the interface between ferromagnetic transition metals and metallic oxides was investigated via first-principles calculations. In this work very large values of PMA, up to 3 erg/cm2, at Fe|MgO interfaces are reported, in agreement with recent experiments. The origin of PMA is attributed to overlap between O-pz and transition metal dz2 orbitals hybridized with dxz(yz) orbitals with stronger spin-orbit coupling-induced splitting around the Fermi level for perpendicular magnetization orientation. Furthermore, it is shown that the PMA value weakens in the case of over- or underoxidation due to the fact that oxygen pz and transition metal dz2 orbital overlap is strongly affected by disorder, in agreement with experimental observations in magnetic tunnel junctions.

Citation
First-principles investigation of the very large perpendicular magnetic anisotropy at Fe | MgO and Co | MgO interfaces 2011, 84 (5) Physical Review B

Publisher
American Physical Society (APS)

Journal
Physical Review B

DOI
10.1103/PhysRevB.84.054401

arXiv
1011.5667

Additional Links
http://link.aps.org/doi/10.1103/PhysRevB.84.054401http://arxiv.org/abs/1011.5667

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