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arXiv · 1610.02767

Origin of magnetic anisotropy in doped Ce$_2$Co$_{17}$ alloys

Liqin Ke·D. A. Kukusta·Duane D. Johnson
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Abstract

Magnetocrystalline anisotropy (MCA) in doped Ce$_{2}$Co$_{17}$ and other competing structures was investigated using density functional theory. We confirmed that the MCA contribution from dumbbell Co sites is very negative. Replacing Co dumbbell atoms with a pair of Fe or Mn atoms greatly enhance the uniaxial anisotropy, which agrees quantitatively with experiment, and this enhancement arises from electronic-structure features near the Fermi level, mostly associated with dumbbell sites. With Co dumbbell atoms replaced by other elements, the variation of anisotropy is generally a collective effect and contributions from other sublattices may change significantly. Moreover, we found that Zr doping promotes the formation of 1-5 structure that exhibits a large uniaxial anisotropy, such that Zr is the most effective element to enhance MCA in this system.

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Liqin Ke, D. A. Kukusta, Duane D. Johnson. 2018-04-10. Origin of magnetic anisotropy in doped Ce$_2$Co$_{17}$ alloys. https://doi.org/10.1103/physrevb.94.144429

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