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Magnetic field-induced quantum critical point in YbPtIn and YbPt$_{0.98}$In single crystals

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 نشر من قبل Emilia Morosan
 تاريخ النشر 2005
  مجال البحث فيزياء
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Detailed anisotropic (H$parallel$ab and H$parallel$c) resistivity and specific heat measurements were performed on online-grown YbPtIn and solution-grown YbPt$_{0.98}$In single crystals for temperatures down to 0.4 K, and fields up to 140 kG; H$parallel$ab Hall resistivity was also measured on the YbPt$_{0.98}$In system for the same temperature and field ranges. All these measurements indicate that the small change in stoichiometry between the two compounds drastically affects their ordering temperatures (T$_{ord}approx3.4$ K in YbPtIn, and $sim2.2$ K in YbPt$_{0.98}$In). Furthermore, a field-induced quantum critical point is apparent in each of these heavy fermion systems, with the corresponding critical field values of YbPt$_{0.98}$In (H$^{ab}_c$ around 35-45 kG and H$^{c}_capprox120$ kG) also reduced compared to the analogous values for YbPtIn (H$^{ab}_capprox60$ kG and H$^{c}_c>140$ kG)



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