Carbon p-electron induced magnetic ordering in Zn-implanted 6H-SiC: experimental observation and theoretical calculation
Carbon p-electron induced magnetic ordering in Zn-implanted 6H-SiC: experimental observation and theoretical calculation
复制标题
掺锌 6H-SiC 中碳 p 电子感应磁有序化：实验观察和理论计算
DOI：
10.1088/2053-1591/3/5/056103
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发表时间：
2016
影响因子：
2.3
通讯作者：
Ye Bangjiao
中科院分区：
文献类型：
--
作者：
Li Qiang;Xu Juping;Liu Ji;ang;Ye Bangjiao
我们观察到锌离子轰击下的6H-SiC晶体有清晰的铁磁有序，并对该样品的磁性进行了详细的研究。从500℃退火到1100℃退火，6H-SiC的磁化强度随退火温度的升高而下降，同时，1100℃退火后，氧穿透晶格并与si键结合。利用基于密度泛函理论的从头计算，我们证实了Zn离子在铁磁性的起源中起作用，而局域矩主要来自围绕外来粒子（本研究中为Zn）的C2p电子。在室温下，硅空位可以提供约2.0 μB/V Si的局域矩，并形成稳定的铁磁相互作用。氧可以促进这种耦合，不再需要V - c调解。计算结果与实验结果吻合较好。我们得出结论，在6H-SiC晶体的任何微观结构中，悬空的C2p键是磁性有序的根本原因。在这种碳基材料中，外来杂质的类型不是磁性起源的关键因素。
We observed clear ferromagnetic ordering in 6H–SiC crystal bombarded with zinc ions, and presented a detailed investigation of magnetic properties in this sample. The magnetization of Zn-implanted 6H–SiC fell and rose with annealing temperature from 500 C to 1100 C. Meanwhile, amount of oxygen penetrated lattices and combined with Si-bonds after 1100 C annealing. Using ab initio calculations based on density functional theory, we confirm that Zn ions play a role in the origin of ferromagnetism, while the localized moment is mainly comes from C2p electrons surrounding the foreign particle (which is Zn in this work). Silicon vacancies can provide localized moment about 2.0 μB/V Si and form stable ferromagnetic interaction at room temperature. Oxygen may facilitate this coupling and no need of V C-mediation any more. The calculations are consistent with experimental results. We concluded that the dangling C2p bonds are fundamental cause of magnetic ordering in whatever microstructures in 6H–SiC crystal. The type of foreign impurities is not crucial factor for the magnetic origin in such carbon-based materials.