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arXiv · 1908.02311

Densities of states in Fe-doped III-V semiconductors: a first-principles study

Shoya Sakamoto·Atsushi Fujimori
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Abstract

The electronic structures of Fe-doped III-V semiconductors were studied by first-principles supercell calculation. It was found that their electronic structures are basically the same as those of Mn-doped ones except that the extra electron of Fe compared to Mn occupies either majority-spin $p$-$d$ hybridized antibonding states ($t_{a,\uparrow}$) or minority-spin $e$ states ($e_{\downarrow}$) and that the center of gravity of the $d$ partial density of states is higher for Fe than for Mn. The present calculations suggest that ferromagnetism appears when the $e_{\downarrow}$ states start to be occupied. The band splitting due to $s$-$d$ hybridization was found to be significantly smaller than the one due to $p$-$d$ hybridization. This indicates that the $s,p$-$d$ exchange interaction is not responsible for the high-temperature ferromagnetism of the Fe-doped ferromagnetic semiconductors even in $n$-type compounds.

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Shoya Sakamoto, Atsushi Fujimori. 2019-08-06. Densities of states in Fe-doped III-V semiconductors: a first-principles study. https://doi.org/10.1063/1.5124704

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