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Magnetic Anisotropy of Co2+ as Signature of Intrinsic Ferromagnetism in ZnO:Co

P. Sati·R. Hayn·R. Kuzian·S. Regnier·S. Schafer·A. Stepanov·C. Morhain·C. Deparis·M. Laugt·M. Goiran·Z. Golacki
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Abstract

We report on the magnetic properties of thoroughly characterized Zn1-xCoxO epitaxial thin films, with low Co concentration, x=0.003-0.005. Magnetic and EPR measurements, combined with crystal field theory, reveal that isolated Co2+ ions in ZnO possess a strong single ion anisotropy which leads to an "easy plane" ferromagnetic state when the ferromagnetic Co-Co interaction is considered. We suggest that the peculiarities of the magnetization process of this state can be viewed as a signature of intrinsic ferromagnetism in ZnO:Co materials.

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P. Sati, R. Hayn, R. Kuzian, S. Regnier, S. Schafer, A. Stepanov, C. Morhain, C. Deparis, M. Laugt, M. Goiran, Z. Golacki. 2007-02-17. Magnetic Anisotropy of Co2+ as Signature of Intrinsic Ferromagnetism in ZnO:Co. https://arxiv.org/abs/cond-mat/0702410

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