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arXiv · 1011.3658

Ferromagnetism in Dilute Magnetic Semiconductors

R. da Silva Neves·A. Ferreira da Silva·R. Kishore
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Abstract

We study the ferromagnetism of Ga1-xMnxAs by using a model Hamiltonian, based on an impurity band and the anti-ferromagnetic exchange interaction between the spins of Mn atoms and the charge carriers in the impurity band. Based on the mean field approach we calculate the spontaneous magnetization as a function of temperature and the ferromagnetic transition temperature as a function of the Mn concentration. The random distribution of Mn impurities is taken into account by Matsubara and Toyozawa theory of impurities in semiconductors. We compare our results with experiments and other theoretical findings.

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R. da Silva Neves, A. Ferreira da Silva, R. Kishore. 2010-11-16. Ferromagnetism in Dilute Magnetic Semiconductors. https://arxiv.org/abs/1011.3658

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