Half-metallic ferromagnetism in Cu-doped ZnO: Density functional calculations
Half-metallic ferromagnetism in Cu-doped ZnO: Density functional calculations
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DOI：
10.1103/physrevb.73.033203
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发表时间：
2006-01
影响因子：
3.7
通讯作者：
L. Ye;A. Freeman;B. Delley
中科院分区：
文献类型：
--
作者：
L. Ye;A. Freeman;B. Delley
利用精确的全势线性化增广平面波和密度泛函理论预测了cu掺杂ZnO的半金属铁磁性。得到了每铜的净磁矩。在Cu浓度为12.5%时，总能量计算表明铁磁态低于反铁磁态，因此预测为基态，估计约为。磁矩定位于铜和氧之间的铁磁耦合的四面体内，附近的电子态由o和Cu之间的强杂化支配，这表明Cu- o键是相当共价的，而不是纯离子键。我们研究了载流子密度和铁磁性之间的相互作用，其中N共掺杂和氧空位之间没有明显的关系。氧空位容易破坏铁磁性，因此在样品制作过程中应避免使用。我们没有发现铜原子的聚类倾向。由于该化合物中没有磁性元素，cu掺杂ZnO似乎是一种明确的稀磁性半导体，可以避免铁磁性沉淀问题。
Half-metallic ferromagnetism in Cu-doped ZnO is predicted by accurate full-potential linearized augmented plane-wave andcalculations based on density functional theory. A net magnetic moment ofis found per Cu. At a Cu concentration of 12.5%, total energy calculations show that the ferromagnetic state islower than the antiferromagnetic state and is thus predicted to be the ground state with aestimated to be about. The magnetic moments are localized within thetetrahedron with ferromagnetic coupling between Cu and O. The electronic states nearare dominated by strong hybridization between Oand Cuwhich implies that the Cu-O bond is quite covalent instead of purely ionic. We examine the interplay between the carrier density and the ferromagnetism with N codoping and oxygen vacancies where we find no apparent relation between them. Oxygen vacancies tend to destroy the ferromagnetism and therefore should be avoided during sample fabrication. We found no clustering tendency of the Cu atoms. Since there is no magnetic element in this compound, Cu-doped ZnO appears to be an unambiguous dilute magnetic semiconductor where ferromagnetic precipitate problems can be avoided.