Spin interactions in direct-gap semiconductors
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摘要: 运用精确的量子蒙特卡洛技术,研究了直接带隙半导体系统(Haldane-Anderson模型)中的磁相互作用.精确的数值解揭示了两种截然不同的自旋关联函数,均没有显示出明显的RKKY振荡行为;并且随着不同参数的变化,自旋关联函数呈现相当复杂的多因素控制的显著特征.这些行为对于理解一些磁性的半导体系统会有很大帮助,例如,稀磁半导体等.
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关键词:
- 量子蒙特卡洛 /
- 直接带隙半导体 /
- Haldane-Anderson模型 /
- RKKY
Abstract: This paper studied spin interactions in a direct-gap system with the two-impurity Haldane-Anderson model, by using exact quantum Monte Carlo method. Exact numerical results revealed two types of magnetic correlation functions, and none of them showed clearly RKKY-type oscillatory behavior. Besides, it was observed that magnetic correlation in the system was complicated and multifactor controlled. The complex magnetic behaviors observed in this study would be helpful for understanding the magnetic properties of a gaped system, snch as the dilute magnetic semiconductors.-
Key words:
- quantum Monte Carlo /
- direct-gap semiconductors /
- Haldane-Anderson model /
- RKKY
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