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First-Principles Prediction of Novel Magnetic Materials Based on ZrCuSiAs-like Semiconducting Pnictide-Oxides

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 نشر من قبل Igor Shein
 تاريخ النشر 2010
  مجال البحث فيزياء
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We assumed that significant enlargement of the functional properties of the family of quaternary ZrCuSiAs-like pnictide-oxides, often called also as 1111 phases, which are known now first of all as parent phases for new FeAs superconductors, may be achieved by replacement of nonmagnetic ions by magnetic ions in semiconducting ZrCuSiAs-like phases. We checked this assumption by means of first-principles FLAPW-GGA calculations using a wide-band-gap semiconductor YZnAsO doped with Mn, Fe, and Co as an example. Our main finding is that substitution of Mn, Fe, and Co for Zn leads to drastic transformations of electronic and magnetic properties of the parent material: as distinct from the non-magnetic YZnAsO, the examined doped phases YZn0.89Mn0.11AsO, YZn0.89Fe0.11AsO, and YZn0.89Co0.11AsO behave as a magnetic semiconductor, a magnetic half-metal or as a magnetic gapless semi-metal, respectively.



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