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arXiv · 1105.0849

Diffusion of Mn interstitials in (Ga,Mn)As epitaxial layers

L. Horák·J. Matějová·X. Martí·V. Holý·V. Novák·Z. Šobáň·S. Mangold·F. Jiménez-Villacorta
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Abstract

Magnetic properties of thin (Ga,Mn)As layers improve during annealing by out-diffusion of interstitial Mn ions to a free surface. Out-diffused Mn atoms participate in the growth of a Mn-rich surface layer and a saturation of this layer causes an inhibition of the out-diffusion. We combine high-resolution x-ray diffraction with x-ray absorption spectroscopy and a numerical solution of the diffusion problem for the study of the out-diffusion of Mn interstitials during a sequence of annealing steps. Our data demonstrate that the out-diffusion of the interstitials is substantially affected by the internal electric field caused by an inhomogeneous distribution of charges in the (Ga,Mn)As layer.

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L. Horák, J. Matějová, X. Martí, V. Holý, V. Novák, Z. Šobáň, S. Mangold, F. Jiménez-Villacorta. 2011-05-04. Diffusion of Mn interstitials in (Ga,Mn)As epitaxial layers. https://doi.org/10.1103/physrevb.83.245209

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