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arXiv · 1304.5323

Effects of composition and chemical disorder on the magnetocrystalline anisotropy of Fe_{x}Pt_{1-x} alloys

C. J. Aas·L. Szunyogh·R. W. Chantrell
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Abstract

We perform first principles calculations of the magnetocrystalline anisotropy energy (MAE) of the L1_{0}-like Fe_{x}Pt_{1-x} samples studied experimentally by Barmak and co-workers in [J. Appl. Phys. 98 (2005) 033904]. The variation of composition and long-range chemical order in the samples was studied in terms of the coherent potential approximation. In accordance with experimental observations, we find that, in the presence of long-range chemical disorder, Fe-rich samples exhibit a larger MAE than stoichiometric FePt. By considering the site- and species-resolved contributions to the MAE, we infer that the MAE is primarily a function of the degree of completeness of the nominal Fe layers in the L1_{0} FePt structure.

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C. J. Aas, L. Szunyogh, R. W. Chantrell. 2013-04-19. Effects of composition and chemical disorder on the magnetocrystalline anisotropy of Fe_{x}Pt_{1-x} alloys. https://doi.org/10.1209/0295-5075%2F102%2F57004

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