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Evolution of helimagnetic correlations in Mn$_{1-x}$Fe$_x$Si with doping: a small-angle neutron scattering study

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 نشر من قبل Lars Bannenberg
 تاريخ النشر 2018
  مجال البحث فيزياء
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We present a comprehensive small angle neutron scattering study of the doping dependence of the helimagnetic correlations in Mn$_{1-x}$Fe$_{x}$Si. The long-range helimagnetic order in Mn$_{1-x}$Fe$_x$Si is suppressed with increasing Fe content and disappears for $x$ $>$ $x^*$ $approx$ 0.11, i.e. well before $x_C$ $approx$ 0.17 where the transition temperature vanishes. For $x$ $>$ $x^*$, only finite isotropic helimagnetic correlations persist which bear similarities with the magnetic correlations found in the precursor phase of MnSi. Magnetic fields gradually suppress and partly align these short-ranged helimagnetic correlations along their direction through a complex magnetization process.



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