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c-axis Tunneling in Nb/Au/YBaCuO Structures

P. V. Komissinski·G. A. Ovsyannikov·N. A. Tulina·V. V. Ryazanov
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Abstract

We present the experimental results for Nb/Au/YBaCuO structures, in which the current flows along (001) direction of YBaCuO film. The theoretical evaluations show, that at the experimental values of the Au/YBaCuO interface transparency, determined from the interface resistance D~10^-6, the critical current of the structure is of the fluctuation order of magnitude due to the sharp decrease of the amplitude potential of the superconducting carriers on this interface. Obtained I-V-curves could be interpreted in terms of contact between d-type pairing superconductor or gapless isotropic superconductor with normal metal. No critical current was observed for investigated structures with characteristic interface resistance RnS~10^-6 Ohm cm^2, 2 orders of magnitude lower, than for known experimental data. PACS: 74.50.+r, 74.72.Bk

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P. V. Komissinski, G. A. Ovsyannikov, N. A. Tulina, V. V. Ryazanov. 1999-03-03. c-axis Tunneling in Nb/Au/YBaCuO Structures. https://arxiv.org/abs/cond-mat/9903065

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