arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1207.2887cond-mat.str-elcond-mat.mtrl-sci
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Mn/$_x$/Ga $_{1-x}$中的电子关联用共振电子能谱和动力学平均场论研究

Electron correlations in Mn$_x$Ga$_{1-x}$As as seen by resonant electron spectroscopy and dynamical mean field theory

I. Di Marco, P. Thunström, M. I. Katsnelson, J. Sadowski, K. Karlsson, S. Lebègue, J. Kanski, O. Eriksson

摘要:

在Mn掺杂GaAs中发现铁磁性20年后,其起源仍然存在争议,许多疑问与电子结构有关。在这里,我们报告的Mn掺杂GaAs的价电子能谱的实验和理论研究。实验数据是通过非共振和共振光电子发射数据之间的差异获得的。理论谱的计算是通过密度泛函理论的局部密度近似和动力学平均场论(LDA+DMFT)的组合,使用精确对角化作为杂质求解器。理论被发现准确地再现测量数据,并说明相关效应的重要性。我们的研究结果表明,Mn态延伸在一个广泛的能量范围内,包括价带的顶部,并且没有杂质带分裂从价带边缘,而诱导的空穴似乎主要位于周围的Mn杂质。

英文摘要:

After two decades from the discovery of ferromagnetism in Mn-doped GaAs, its origin is still debated, and many doubts are related to the electronic structure. Here we report an experimental and theoretical study of the valence electron spectrum of Mn-doped GaAs. The experimental data are obtained through the differences between off- and on-resonance photo-emission data. The theoretical spectrum is calculated by means of a combination of density-functional theory in the local density approximation and dynamical mean-field theory (LDA+DMFT), using exact diagonalisation as impurity solver. Theory is found to accurately reproduce measured data, and illustrates the importance of correlation effects. Our results demonstrate that the Mn states extend over a broad range of energy, including the top of the valence band, and that no impurity band splits off from the valence band edge, while the induced holes seem located primarily around the Mn impurity.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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