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Magnetic-field effects in defect-controlled ferromagnetic Ga_{1-x}Mn_xAs semiconductors

Raimundo R. dos Santos·J. d'Albuquerque e Castro·L. E. Oliveira
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Abstract

We have studied the magnetic-field and concentration dependences of the magnetizations of the hole and Mn subsystems in diluted ferromagnetic semiconductor Ga_{1-x}Mn_xAs. A mean-field approximation to the hole-mediated interaction is used, in which the hole concentration p(x) is parametrized in terms of a fitting (of the hole effective mass and hole/local moment coupling) to experimental data on the Tc critical temperature. The dependence of the magnetizations with x, for a given temperature, presents a sharply peaked structure, with maxima increasing with applied magnetic field, which indicates that application to diluted-magnetic-semiconductor devices would require quality-control of the Mn-doping composition. We also compare various experimental data for Tc(x) and p(x) on different Ga_{1-x}Mn_xAs samples and stress the need of further detailed experimental work to assure that the experimental measurements are reproducible.

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Raimundo R. dos Santos, J. d'Albuquerque e Castro, L. E. Oliveira. 2003-01-13. Magnetic-field effects in defect-controlled ferromagnetic Ga_{1-x}Mn_xAs semiconductors. https://doi.org/10.1063/1.1534622

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