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Phonon-induced quadrupolar ordering of the magnetic superconductor TmNi$_2$B$_2$C

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 نشر من قبل Jens Jensen
 تاريخ النشر 2005
  مجال البحث فيزياء
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We present synchrotron x-ray diffraction studies revealing that the lattice of thulium borocarbide is distorted below T_Q = 13.5 K at zero field. T_Q increases and the amplitude of the displacements is drastically enhanced, by a factor of 10 at 60 kOe, when a magnetic field is applied along [100]. The distortion occurs at the same wave vector as the antiferromagnetic ordering induced by the a-axis field. A model is presented that accounts for the properties of the quadrupolar phase and explains the peculiar behavior of the antiferromagnetic ordering previously observed in this compound.



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