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arXiv · 0911.3678

Influence of aging on fishtail-effect in pure and Ag-doped MG-YBCO

D. Lotnyk·R. V. Vovk·M. A. Obolenskii·A. A. Zavgorodniy·J. Kovac·V. Antal·M. Kanuchova·M. Sefcikova·P. Diko·A. Feher
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Abstract

$M(B)$-curves were experimentally investigated. Fishtail-effect (FE) was observed in MG YBa$_2$Cu$_3$O$_{7-δ}$ and YBa$_2$(Cu$_{1-x}$Ag$_x$)$_3$O$_{7-δ}$ (at $x \approx$ 0.02) crystals in a wide temperature range 0.4 $<T/T_c<$ 0.8 at the orientation of magnetic field $\textbf{H}\parallel c$. It was obtained that the influence of bulk pinning on FE is more effective at low temperatures while surface barriers dominates at high temperatures. The value $H_{max}$ for Ag-doped crystals is larger than for a pure one that due to the presence of additional pinning centers, above all on silver atoms.

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D. Lotnyk, R. V. Vovk, M. A. Obolenskii, A. A. Zavgorodniy, J. Kovac, V. Antal, M. Kanuchova, M. Sefcikova, P. Diko, A. Feher. 2009-11-18. Influence of aging on fishtail-effect in pure and Ag-doped MG-YBCO. https://arxiv.org/abs/0911.3678

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