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arXiv · 1501.03483

Origin of the spin reorientation transitions in (Fe$_{1-x}$Co$_{x}$)$_{2}$B alloys

Kirill D. Belashchenko·Liqin Ke·Markus Däne·Lorin X. Benedict·Tej Nath Lamichhane·Valentin Taufour·Anton Jesche·Sergey L. Bud'ko·Paul C. Canfield·Vladimir P. Antropov
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Abstract

Low-temperature measurements of the magnetocrystalline anisotropy energy $K$ in (Fe$_{1-x}$Co$_{x}$)$_{2}$B alloys are reported, and the origin of this anisotropy is elucidated using a first-principles electronic structure analysis. The calculated concentration dependence $K(x)$ with a maximum near $x=0.3$ and a minimum near $x=0.8$ is in excellent agreement with experiment. This dependence is traced down to spin-orbital selection rules and the filling of electronic bands with increasing electronic concentration. At the optimal Co concentration, $K$ depends strongly on the tetragonality and doubles under a modest 3% increase of the $c/a$ ratio, suggesting that the magnetocrystalline anisotropy can be further enhanced using epitaxial or chemical strain.

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Kirill D. Belashchenko, Liqin Ke, Markus Däne, Lorin X. Benedict, Tej Nath Lamichhane, Valentin Taufour, Anton Jesche, Sergey L. Bud'ko, Paul C. Canfield, Vladimir P. Antropov. 2015-02-03. Origin of the spin reorientation transitions in (Fe$_{1-x}$Co$_{x}$)$_{2}$B alloys. https://doi.org/10.1063/1.4908056

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