Groupe de Physique des Matériaux, UMR 6634 CNRS, Université et INSA de Rouen , Avenue de l'Université, B.P. 12, 76801 Saint Etienne du Rouvray, France.
J Am Chem Soc. 2011 Feb 9;133(5):1451-8. doi: 10.1021/ja108290u. Epub 2011 Jan 5.
Nanosized Co clusters (of about 3 nm size) were unambiguously identified in Co-doped ZnO thin films by atom probe tomography. These clusters are directly correlated to the superparamagnetic relaxation observed by ZFC/FC magnetization measurements. These analyses provide strong evidence that the room-temperature ferromagnetism observed in the magnetization curves cannot be attributed to the observed Co clusters. Because there is no experimental evidence of the presence of other secondary phases, our results reinforce the assumption of a defect-induced ferromagnetism in Co-doped ZnO diluted magnetic semiconductors.
通过原子探针断层摄影术，在掺钴氧化锌薄膜中明确地识别出纳米级 Co 团簇（约 3nm 大小）。这些团簇与 ZFC/FC 磁化测量中观察到的超顺磁弛豫直接相关。这些分析为室温铁磁性不能归因于观察到的 Co 团簇提供了有力的证据。因为没有实验证据表明存在其他次要相，所以我们的结果加强了 Co 掺杂 ZnO 稀磁半导体中缺陷诱导铁磁性的假设。
