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arXiv · 1405.0499

Jahn-Teller driven perpendicular magnetocrystalline anisotropy in metastable Ruthenium

Dorj Odkhuu·S. H. Rhim·N. Park·Kohji Nakamura·S. C. Hong
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Abstract

A new metastable phase of the body-centered-tetragonal ruthenium ({\em bct}--Ru) is identified to exhibit a large perpendicular magnetocrystalline anisotropy (PMCA), whose energy, $E_{MCA}$, is as large as 150 $\mu$eV/atom, two orders of magnitude greater than those of 3$d$ magnetic metals. Further investigation over the range of tetragonal distortion suggests that the appearance of the magnetism in the {\em bct}--Ru is governed by the Jahn-Teller spit $e_g$ orbitals. Moreover, from band analysis, MCA is mainly determined by an interplay between two $e_g$ states, $d_{x^2-y^2}$ and $d_{z^2}$ states, as a result of level reversal associated with tetragonal distortion.

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Dorj Odkhuu, S. H. Rhim, N. Park, Kohji Nakamura, S. C. Hong. 2014-05-02. Jahn-Teller driven perpendicular magnetocrystalline anisotropy in metastable Ruthenium. https://doi.org/10.1103/physrevb.91.014437

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