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arXiv · supr-con/9606003

Plastic vortex-creep in YBa$_2$Cu$_3$O$_{7-x}$ crystals

Y. Abulafia·A. Shaulov·Y. Wolfus·R. Prozorov·L. Burlachkov·Y. Yeshurun·D. Majer E. Zeldov·H. Wühl·V. B. Geshkenbein·V. M. Vinokur
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Abstract

Local magnetic relaxation measurements in YBa$_2$Cu$_3$O$_{7-x}$ crystals show evidence for plastic vortex-creep associated with the motion of dislocations in the vortex lattice. This creep mechanism governs the vortex dynamics in a wide range of temperatures and fields below the melting line and above the field corresponding to the peak in the ''fishtail'' magnetization. In this range the activation energy $U_{pl}$, which decreases with field, drops below the elastic (collective) creep activation energy, $U_{el}$, which increases with field. A crossover in flux dynamics from elastic to plastic creep is shown to be the origin of the fishtail in YBa$_2$Cu$_3$O$_{7-x}$.

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Y. Abulafia, A. Shaulov, Y. Wolfus, R. Prozorov, L. Burlachkov, Y. Yeshurun, D. Majer E. Zeldov, H. Wühl, V. B. Geshkenbein, V. M. Vinokur. 1996-06-22. Plastic vortex-creep in YBa$_2$Cu$_3$O$_{7-x}$ crystals. https://doi.org/10.1103/physrevlett.77.1596

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