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arXiv · 1012.4690

Detection of stacking faults breaking the [110]/[1-10] symmetry in ferromagnetic semiconductors (Ga,Mn)As and (Ga,Mn)(As,P)

M. Kopecky·J. Kub·F. Maca·J. Masek·O. Pacherova·B. L. Gallagher·R. P. Campion·V. Novak·T. Jungwirth
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Abstract

We report high resolution x-ray diffraction measurements of (Ga,Mn)As and (Ga,Mn)(As,P) epilayers. We observe a structural anisotropy in the form of stacking faults which are present in the (111) and (11-1) planes and absent in the (-111) and (1-11) planes. The stacking faults produce no macroscopic strain. They occupy 0.01 - 0.1 per cent of the epilayer volume. Full-potential density functional calculations evidence an attraction of Mn_Ga impurities to the stacking faults. We argue that the enhanced Mn density along the common [1-10] direction of the stacking fault planes produces sufficiently strong [110]/[1-10] symmetry breaking mechanism to account for the in-plane uniaxial magnetocrystalline anisotropy of these ferromagnetic semiconductors.

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M. Kopecky, J. Kub, F. Maca, J. Masek, O. Pacherova, B. L. Gallagher, R. P. Campion, V. Novak, T. Jungwirth. 2010-12-21. Detection of stacking faults breaking the [110]/[1-10] symmetry in ferromagnetic semiconductors (Ga,Mn)As and (Ga,Mn)(As,P). https://doi.org/10.1103/physrevb.83.235324

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