Título:
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Reversible ferromagnetic switching in ZnO:(Co,Mn) powders
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Autor/a:
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Rubí, D.; Fontcuberta i Griñó, Josep; Calleja Lázaro, Alberto; Aragonès, Ll.; Garcia Capdevila, Xavier; Segarra Rubí, Mercè
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Otros autores:
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Universitat de Barcelona |
Abstract:
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We report here on the magnetic properties of ZnO:Mn- and ZnO:Co-doped nanoparticles. We have found that the ferromagnetism of ZnO:Mn can be switched on and off by consecutive low-temperature annealings in O2 and N2, respectively, while the opposite phenomenology was observed for ZnO:Co. These results suggest that different defects (presumably n-type for ZnO:Co and p-type for ZnO:Mn) are required to induce a ferromagnetic coupling in each case. We will argue that ferromagnetism is likely to be restricted to a very thin, nanometric layer at the grain surface. These findings reveal and give insight into the dramatic relevance of surface effects to the occurrence of ferromagnetism in ZnO-doped oxides. |
Materia(s):
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-Materials -Propietats magnètiques -Magnetic properties and materials |
Derechos:
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(c) The American Physical Society, 2007
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Tipo de documento:
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Artículo Artículo - Versión publicada |
Editor:
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The American Physical Society
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