Comment on "Effects of Disorder on Ferromagnetism in Diluted Magnetic Semiconductors"

C. Timm; F. Schäfer; F. von Oppen

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Comment on "Effects of Disorder on Ferromagnetism in Diluted Magnetic Semiconductors"

C. Timm·F. Schäfer·F. von Oppen

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Abstract

In a recent Letter, Berciu and Bhatt have presented a mean-field theory of ferromagnetism in III-V semiconductors doped with manganese, starting from an impurity band model. We show that this approach gives an unphysically broad impurity band and is thus not appropriate for (Ga,Mn)As containing 1-5% Mn. We also point out a microscopically unmotivated sign change in the overlap integrals in the Letter. Without this sign change, stable ferromagnetism is not obtained.

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C. Timm, F. Schäfer, F. von Oppen. 2001-11-27. Comment on "Effects of Disorder on Ferromagnetism in Diluted Magnetic Semiconductors". https://arxiv.org/abs/cond-mat/0111504

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