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In-plane uniaxial anisotropy rotations in (Ga,Mn)As thin films

M. Sawicki·K-Y. Wang·K. W. Edmonds·R. P. Campion·C. R. Staddon·N. R. S. Farley·C. T. Foxon·E. Papis·E. Kaminska·A. Piotrowska·T. Dietl·B. L. Gallagher
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Abstract

We show, by SQUID magnetometry, that in (Ga,Mn)As films the in-plane uniaxial magnetic easy axis is consistently associated with particular crystallographic directions and that it can be rotated from the [-110] direction to the [110] direction by low temperature annealing. We show that this behavior is hole-density-dependent and does not originate from surface anisotropy. The presence of uniaxial anisotropy as well its dependence on the hole-concentration and temperature can be explained in terms of the p-d Zener model of the ferromagnetism assuming a small trigonal distortion.

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M. Sawicki, K-Y. Wang, K. W. Edmonds, R. P. Campion, C. R. Staddon, N. R. S. Farley, C. T. Foxon, E. Papis, E. Kaminska, A. Piotrowska, T. Dietl, B. L. Gallagher. 2004-10-21. In-plane uniaxial anisotropy rotations in (Ga,Mn)As thin films. https://doi.org/10.1103/physrevb.71.121302

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