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arXiv · 1212.1781

$Ab~initio$ studies of Co$_2$FeAl$_{1-x}$Si$_x$ Heusler alloys

N. Gonzalez Szwacki·Jacek A. Majewski
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Abstract

We present results of extensive theoretical studies of Co$_2$FeAl$_{1-x}$Si$_x$ Heusler alloys, which have been performed in the framework of density functional theory employing the all-electron full-potential linearized augmented plane-wave scheme. It is shown that the Si-rich alloys are more resistive to structural disorder and as a consequence Si stabilizes the $L2_1$ structure. Si alloying changes position of the Fermi level, pushing it into the gap of the minority spin-band. It is also shown that the hyperfine field on Co nuclei increases with the Si concentration, and this increase originates mostly from the changes in the electronic density of the valence electrons.

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N. Gonzalez Szwacki, Jacek A. Majewski. 2012-12-08. $Ab~initio$ studies of Co$_2$FeAl$_{1-x}$Si$_x$ Heusler alloys. https://doi.org/10.1016/j.jmmm.2016.02.031

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