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High field x-ray diffraction study on a magnetic-field-induced valence transition in YbInCu4

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 نشر من قبل Yasuhiro Matsuda
 تاريخ النشر 2005
  مجال البحث فيزياء
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We report the first high-field x-ray diffraction experiment using synchrotron x-rays and pulsed magnetic fields exceeding 30 T. Lattice deformation due to a magnetic-field-induced valence transition in YbInCu4 is studied. It has been found that the Bragg reflection profile at 32 K changes significantly at around 27 T due to the structural transition. In the vicinity of the transition field the low-field and the high-field phases are observed simultaneously as the two distinct Bragg reflection peaks: This is a direct evidence of the fact that the field-induced valence state transition is the first order phase transition. The field-dependence of the low-field-phase Bragg peak intensity is found to be scaled with the magnetization.

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