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Crystalline Ni nanoparticles as the origin of ferromagnetism in Ni implanted ZnO crystals

Shengqiang Zhou·K. Potzger·Gufei Zhang·F. Eichhorn·W. Skorupa·M. Helm·J. Fassbender
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Abstract

We report the structural and magnetic properties of ZnO single crystals implanted at 623 K with up to 10 at. % of Ni. As revealed by X-ray diffraction, crystalline fcc-Ni nanoparticles were formed inside ZnO. The magnetic behavior (magnetization with field reversal and with different temperature protocol) of all samples is well explained by a magnetic Ni-nanoparticle system. Although the formation of Ni:ZnO based diluted magnetic semiconductor cannot be ruled out, the major contribution to the magnetic properties stems from crystalline nanoparticles synthesized under these implantation conditions.

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Shengqiang Zhou, K. Potzger, Gufei Zhang, F. Eichhorn, W. Skorupa, M. Helm, J. Fassbender. 2006-11-30. Crystalline Ni nanoparticles as the origin of ferromagnetism in Ni implanted ZnO crystals. https://doi.org/10.1063/1.2396763

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