Aggregation-based growth and magnetic properties of inhomogeneous Cu-doped ZnO nanocrystals
Aggregation-based growth and magnetic properties of inhomogeneous Cu-doped ZnO nanocrystals
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DOI：
10.1063/1.2741408
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发表时间：
2007-05
影响因子：
4
通讯作者：
Xuefeng Wang;Jianbin Xu;W. Cheung;J. An;N. Ke
中科院分区：
文献类型：
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作者：
Xuefeng Wang;Jianbin Xu;W. Cheung;J. An;N. Ke
报道了用溶剂热法合成的1.86at.%掺铜氧化锌纳米晶的铁磁有序性。铜在氧化锌晶格中的分布不均匀。在贫铜芯中，提出了自旋分裂受主杂质带模型来解释铁磁性。而在富铜表面层，非完全取向附着产生的浅施主类缺陷不仅补偿了少数空穴，而且容易占据Cu3d态破坏CuO4四面体，从而形成短程反铁磁团簇。结果，在铁磁/反铁磁界面处发生了有趣的交换偏置现象。
The authors report on the ferromagnetic ordering in 1.86at.% Cu-doped ZnO nanocrystals synthesized by a solvothermal route. The distribution of Cu in ZnO lattice was inhomogeneous. In the Cu-poor cores, a spin-split acceptor impurity band model was proposed to explain the ferromagnetism. While in the Cu-rich surface layers, the shallow donorlike defects generated by imperfect oriented attachment could not only compensate a few holes but also readily occupy the Cu 3d states to destroy CuO4 tetrahedra, hence resulting in the short-range antiferromagnetic clusters. As a result, an interesting exchange biasing phenomenon took place at the ferromagnetic/antiferromagnetic interface.