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arXiv · 0906.3502

Origin of large moments in Mn$_x$Si$_{1-x}$ at small x

Michael Shaughnessy·C. Y. Fong·Ryan Snow·Kai Liu·John Pask·Lin H. Yang
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Abstract

Recently, the magnetic moment/Mn, $M$, in Mn$_x$Si$_{1-x}$ was measured to be 5.0 $\mu_B$/Mn, at $x$ =0.1%. To understand this observed $M$, we investigate several Mn$_x$Si$_{1-x}$ models of alloys using first-principles density functional methods. The only model giving $M = 5.0$ was a 513-atom cell having the Mn at a substitutional site, and Si at a second-neighbor interstitial site. The observed large moment is a consequence of the weakened d-p hybridization between the Mn and one of its nearest neighbor Si atoms, resulting from the introduction of the second-neighbor interstitial Si. Our result suggests a way to tune the magnetic moments of transition metal doped semiconductors.

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Michael Shaughnessy, C. Y. Fong, Ryan Snow, Kai Liu, John Pask, Lin H. Yang. 2009-06-18. Origin of large moments in Mn$_x$Si$_{1-x}$ at small x. https://doi.org/10.1063/1.3168512

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