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Emergence of spin-orbit order in the spinel CuCr$_2$O$_4$

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 نشر من قبل Keisuke Tomiyasu
 تاريخ النشر 2018
  مجال البحث فيزياء
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We determined the magnetic structure of CuCr$_2$O$_4$ using neutron diffraction and irreducible representation analysis. The measurements identified a new phase between 155 K and 125 K as nearly collinear magnetic ordering in the Cr pyrochlore lattice. Below 125 K, a Cu-Cr ferrimagnetic component develops the noncollinear order. Along with the simultaneously obtained O positions and the quantum effect of spin-orbit coupling, the magnetic structure is understood to involve spin-orbit ordering, accompanied by an appreciably deformed orbital of presumably spin-only Cu and Cr.



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