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arXiv · 1701.06035

Excess conduction of YBaCuO point contacts between 100 and 200 K

L. F. Rybal'chenko·I. K. Yanson·N. L. Bobrov·V. V. Fisun·M. A. Obolenskii·A. V. Bondarenko·Yu. D. Tret'yakov·A. R. Kaul'·I. E. Graboi
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Abstract

$YBaCuO-Ag$ pressure point contacts with direct conduction are investigated. The excess (relative to the normal state) conductivity mainly caused by fluctuational pairing of electrons above $T_c$ is measured in the temperature interval 100-200~$K$. The superconductivity above 120~$K$ is found to be of the two-dimensional type. The obtained preliminary results indicate the presence of small amount of an unknown phase with $T'_c\gtrsim 200~K$ in $YBaCuO$.

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L. F. Rybal'chenko, I. K. Yanson, N. L. Bobrov, V. V. Fisun, M. A. Obolenskii, A. V. Bondarenko, Yu. D. Tret'yakov, A. R. Kaul', I. E. Graboi. 2017-01-21. Excess conduction of YBaCuO point contacts between 100 and 200 K. https://arxiv.org/abs/1701.06035

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