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Annealing effects on the normal-state resistive properties of underdoped cuprates

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 نشر من قبل Oleksandr Dobrovolskiy V.
 تاريخ النشر 2019
  مجال البحث فيزياء
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The influence of room-temperature annealing on the parameters of the basal-plane electrical resistance of underdoped YBa$_2$Cu$_3$O$_{7-delta}$ and HoBa$_2$Cu$_3$O$_{7-delta}$ single crystals in the normal and superconducting states is investigated. The form of the derivatives $drho(T)/dT$ makes it possible to determine the onset temperature of the fluctuation conductivity and indicates a nonuniform distribution of the labile oxygen. Annealing has been revealed to lead to a monotonic decrease in the oxygen deficiency, that primarily manifests itself as a decrease of the residual resistance, an increase of $T_c$, and a decrease of the Debye temperature.



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