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arXiv · 0704.0694

Current - voltage characteristics of break junctions of high-$T_c$ superconductors

D M Gokhfeld·D A Balaev·K A Shaykhutdinov·S I Popkov·M I Petrov
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Abstract

The current-voltage ($I$-$V$) characteristics of break junctions of polycrystalline La$_{1.85}$Sr$_{0.15}$CuO$_4$, Y$_{0.75}$Lu$_{0.25}$Ba$_2$Cu$_3$O$_{7-δ}$, Bi$_{1.8}$Pb$_{0.3}$Sr$_{1.9}$Ca$_2$Cu$_3$O$_x$ and composite YBa$_2$Cu$_3$O$_{7-δ}$ + Ag are investigated. The experimental $I$-$V$ curves exhibit the specific peculiarities of superconductor/normal-metal/superconductor junctions. The relation between an $I$-$V$ characteristic of network of weak links and $I$-$V$ dependencies of typical weak links is suggested to describe the experimental data. The $I$-$V$ curves of typical weak links are calculated by the Kümmel - Gunsenheimer - Nicolsky model considering the multiple Andreev reflections.

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D M Gokhfeld, D A Balaev, K A Shaykhutdinov, S I Popkov, M I Petrov. 2007-04-05. Current - voltage characteristics of break junctions of high-$T_c$ superconductors. https://doi.org/10.1016/j.physc.2007.09.001

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