Anomalous exchange interactions in III-V dilute magnetic semiconductors
Anomalous exchange interactions in III-V dilute magnetic semiconductors
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DOI：
10.1103/physrevb.63.233205
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发表时间：
2001-05
影响因子：
3.7
通讯作者：
M. Schilfgaarde;O. Mryasov
中科院分区：
文献类型：
--
作者：
M. Schilfgaarde;O. Mryasov
基于局域密度泛函计算，我们研究了磁性掺杂剂Cr，Mn和Fe在III-V族化合物GaAs，GaN和AlN中的交换相互作用。我们发现，磁交换相互作用强烈偏离预期的行为从简单的模型，并可以解释所观察到的最大临界温度与杂质浓度。此外，磁性是负责磁性掺杂剂之间的强，短程吸引力，从而创建一个异常的有效合金哈密顿量。这表明杂质可能聚集成几个磁性原子的小纳米团簇。
Based on local-density functional calculations, we study the exchange interactions between magnetic dopants Cr, Mn, and Fe in the III-V compounds GaAs, GaN, and AlN. We show the magnetic exchange interactions deviate strongly in behavior expected from simple models, and may explain the observed maximum in critical temperature with impurity concentration. Additionally the magnetism is responsible for a strong, short-range attraction between the magnetic dopants, thus creating an anomalous effective alloy hamiltonian. This suggests that the impurities may aggregate into small nanoclusters of a few magnetic atoms.