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arXiv · 0908.2108

Unusually strong coherent response from grain-boundary Josephson network in polycrystalline Pr_{x}Y_{1-x}Ba_2Cu_3O_7

V. A. G. Rivera·S. Sergeenkov·C. Stari·L. Jr. Cichetto·C. A. Cardoso·E. Marega·F. M. Araujo-Moreira
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Abstract

By applying a highly sensitive homemade AC susceptibility technique to Pr_{x}Y_{1-x}Ba_2Cu_3O_7 polycrystals (with x=0.0, 0.1 and 0.3), we observed very sharp Fraunhofer type low-field periodic oscillations of the real part of the AC susceptibility which were attributed to Josephson vortices penetrating intergranular regions of grain-boundary Josephson network in our samples. Assuming the Lorentz type distribution of single-junction contact areas, we were able to successfully fit the experimental data.

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V. A. G. Rivera, S. Sergeenkov, C. Stari, L. Jr. Cichetto, C. A. Cardoso, E. Marega, F. M. Araujo-Moreira. 2009-08-14. Unusually strong coherent response from grain-boundary Josephson network in polycrystalline Pr_{x}Y_{1-x}Ba_2Cu_3O_7. https://doi.org/10.1134/s0021364009170111

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