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arXiv · 0804.3937

Magnetic states at the Oxygen surfaces of ZnO and Co-doped ZnO

N. Sanchez·S. Gallego·M. C. Munoz
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Abstract

First principles calculations of the O surfaces of Co-ZnO show that substitutional Co ions develop large magnetic moments which long-range coupling depends on their mutual distance. The local spin polarization induced at the O atoms is three times larger at the surface than in the bulk, and the surface stability is considerably reinforced by Co. Moreover, a robust ferromagnetic state is predicted at the Oxygen (0001) surface even in the absence of magnetic atoms. The occurrence of surface magnetic moments correlates with the number of {\it p}-holes in the valence band of the oxide, and the distribution of the magnetic charge is, even in the absence of spin-orbit interaction, highly anisotropic.

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N. Sanchez, S. Gallego, M. C. Munoz. 2008-04-24. Magnetic states at the Oxygen surfaces of ZnO and Co-doped ZnO. https://doi.org/10.1103/physrevlett.101.067206

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