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Details of Sample Dependence and Transport Properties of URu2Si2

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 نشر من قبل Tatsuma Matsuda
 تاريخ النشر 2011
  مجال البحث فيزياء
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Resistivity and specific heat measurements were performed in the low carrier unconventional superconductor URu2Si2 on various samples with very different qualities. The superconducting transition temperature (TSC) and the hidden order transition temperature (THO) of these crystals were evaluated as a function of the residual resistivity ratio (RRR). In high quality single crystals the resistivity does not seem to follow a T2 dependence above TSC, indicating that the Fermi liquid regime is restricted to low temperatures. However, an analysis of the isothermal longitudinal magnetoresistivity points out that the T2 dependence may be spoiled by residual inhomogeneous superconducting contribution. We discuss a possible scenario concerning the distribution of TSC related with the fact that the hidden order phase is very sensitive to the pressure inhomogeneity.



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