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Rare-earth impurities in Co$_2$MnSi: an opportunity to improve Half-Metallicity at finite temperatures

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 نشر من قبل Liviu Chioncel
 تاريخ النشر 2010
  مجال البحث فيزياء
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We analyse the effects of doping Holmium impurities into the full-Heusler ferromagnetic alloy Co$_2$MnSi. Experimental results, as well as theoretical calculations within Density Functional Theory in the Local Density Approximation plus Hubbard U framework show that the holmium moment is aligned antiparallely to that of the transition metal atoms. According to the electronic structure calculations, substituting Ho on Co sites introduces a finite density of states in the minority spin gap, while substitution on the Mn sites preserves the half-metallic character.



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