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arXiv · 1108.1294

Ferromagnetic spin coupling of 2p-impurities in band insulators stabilized by intersite Coulomb interaction: Nitrogen-doped MgO

Ivetta Slipukhina·Phivos Mavropoulos·Stefan Blügel·Marjana Ležaić
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Abstract

For a nitrogen dimer in insulating MgO, a ferromagnetic coupling between spin-polarized $2p$-holes is revealed by calculations based on the density functional theory amended by an on-site Coulomb interaction and corroborated by the Hubbard model. It is shown that the ferromagnetic coupling is facilitated by a T-shaped orbital arrangement of the $2p$-holes, which is in its turn controlled by an intersite Coulomb interaction due to the directionality of the $p$-orbitals. We thus conjecture that this interaction is an important ingredient of ferromagnetism in band insulators with $2p$ dopants.

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Ivetta Slipukhina, Phivos Mavropoulos, Stefan Blügel, Marjana Ležaić. 2011-08-05. Ferromagnetic spin coupling of 2p-impurities in band insulators stabilized by intersite Coulomb interaction: Nitrogen-doped MgO. https://doi.org/10.1103/physrevlett.107.137203

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