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Central peak position in magnetization loops of high-$T_c$ superconductors

D. V. Shantsev·M. R. Koblischka·Y. M. Galperin·T. H. Johansen·P. Nalevka·M. Jirsa
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Abstract

Exact analytical results are obtained for the magnetization of a superconducting thin strip with a general behavior J_c(B) of the critical current density. We show that within the critical-state model the magnetization as function of applied field, B_a, has an extremum located exactly at B_a=0. This result is in excellent agreement with presented experimental data for a YBCO thin film. After introducing granularity by patterning the film, the central peak becomes shifted to positive fields on the descending field branch of the loop. Our results show that a positive peak position is a definite signature of granularity in superconductors.

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D. V. Shantsev, M. R. Koblischka, Y. M. Galperin, T. H. Johansen, P. Nalevka, M. Jirsa. 1998-12-14. Central peak position in magnetization loops of high-$T_c$ superconductors. https://doi.org/10.1103/physrevlett.82.2947

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