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arXiv · 1703.08708

Critical current density in the superconducting ceramic $\rm La_{1.8}Sr_{0.2}CuO_4$ in S-c-N point contacts

I. K. Yanson·L. F. Rybal'chenko·N. L. Bobrov·V. V. Fisun
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Abstract

Measurement of the current-voltage characteristics of point contacts makes it possible to study the properties of individual crystallites in a superconducting ceramic. The critical current density in the superconducting regions of the ceramic $\rm La_{1.8}Sr_{0.2}CuO_4$, with a size of the order of several tens of angstroms, is found to attain values of $10^8\ A/cm^2$, which are of the same order of magnitude as the pair-breaking current density, as evaluated from the formulas of the standard theory of superconductivity.

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I. K. Yanson, L. F. Rybal'chenko, N. L. Bobrov, V. V. Fisun. 2017-03-28. Critical current density in the superconducting ceramic $\rm La_{1.8}Sr_{0.2}CuO_4$ in S-c-N point contacts. https://arxiv.org/abs/1703.08708

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