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arXiv · 1901.06193

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

R. V. Vovk·G. Ya. Khadzhai·Z. F. Nazyrov·S. N. Kamchatnaya·O. V. Dobrovolskiy
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Abstract

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 $d\rho(T)/dT$ 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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R. V. Vovk, G. Ya. Khadzhai, Z. F. Nazyrov, S. N. Kamchatnaya, O. V. Dobrovolskiy. 2019-01-18. Annealing effects on the normal-state resistive properties of underdoped cuprates. https://doi.org/10.1007/s10909-018-1856-9

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