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Disorder effects in diluted ferromagnetic semiconductors

G. Bouzerar·J. Kudrnovsky·P. Bruno
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Abstract

Carrier induced ferromagnetism in diluted III-V semi-conductor is analyzed within a two step approach. First, within a single site CPA formalism, we calculate the element resolved averaged Green's function of the itinerant carrier. Then using a generalized RKKY formula we evaluate the Mn-Mn long-range exchange integrals and the Curie temperature as a function of the exchange parameter, magnetic impurity concentration and carrier density. The effect of the disorder (impurity scattering) appears to play a crucial role. The standard RKKY calculation (no scattering processes), strongly underestimate the Curie temperature and is inappropriate to describe magnetism in diluted magnetic semi-conductors. It is also shown that an antiferromagnetic exchange favors higher Curie temperature.

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G. Bouzerar, J. Kudrnovsky, P. Bruno. 2002-08-30. Disorder effects in diluted ferromagnetic semiconductors. https://doi.org/10.1103/physrevb.68.205311

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