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Giant magneto-elastic coupling in a metallic helical metamagnet

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 نشر من قبل Karl Sandeman
 تاريخ النشر 2010
  مجال البحث فيزياء
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Using high resolution neutron diffraction and capacitance dilatometry we show that the thermal evolution of the helimagnetic state in CoMnSi is accompanied by a change in inter-atomic distances of up to 2%, the largest ever found in a metallic magnet. Our results and the picture of competing exchange and strongly anisotropic thermal expansion that we use to understand them sheds light on a new mechanism for large magnetoelastic effects that does not require large spin-orbit coupling.



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