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arXiv · 1901.06171

Room-temperature annealing effects on the basal-plane resistivity of optimally doped YBa$_2$Cu$_3$O$_{7-\delta}$ single crystals

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

We reveal that the temperature dependence of the basal-plane normal-state electrical resistance of optimally doped YBa$_2$Cu$_3$O$_{7-\delta}$ single crystals can be with great accuracy approximated within the framework of the model of s-d electron-phonon scattering. This requires taking into account the fluctuation conductivity whose contribution exponentially increases with decreasing temperature and decreases with an increase of oxygen deficiency. Room-temperature annealing improves the sample and, thus, increases the superconducting transition temperature. The temperature of the 2D-3D crossover decreases during annealing.

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G. Ya. Khadzhai, R. V. Vovk, N. R. Vovk, S. N. Kamchatnaya, O. V. Dobrovolskiy. 2019-01-18. Room-temperature annealing effects on the basal-plane resistivity of optimally doped YBa$_2$Cu$_3$O$_{7-\delta}$ single crystals. https://doi.org/10.1016/j.physc.2017.11.015

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