arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1908.02311cond-mat.str-elcond-mat.mtrl-sci
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Fe掺杂III-V半导体态密度的第一性原理研究

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

Shoya Sakamoto, Atsushi Fujimori

摘要:

采用第一性原理超原胞方法研究了Fe掺杂Ⅲ-Ⅴ族半导体的电子结构。发现它们的电子结构与Mn掺杂的电子结构基本相同,除了Fe的额外电子占据多数自旋$p$杂化反键态($t_{a,\uparrow}$)或少数自旋$e$态($e_{\downarrow}$),并且Fe的$d$分态密度的重心高于Mn。计算结果表明,当$e_{\downarrow}$态开始被占据时,铁磁性出现。发现由$s$杂交引起的条带分裂显著小于由$p$ - $d$杂交引起的条带分裂。这表明,即使在$n$型化合物中,$s,p$ - $d$交换相互作用也不是Fe掺杂铁磁半导体的高温铁磁性的原因。

英文摘要:

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.

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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