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Evidence for vortex staircases in the whole angular range due to competing correlated pinning mechanisms

A. Silhanek·L. Civale·S. Candia·G. Nieva·G. Pasquini·H. Lanza
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Abstract

We analyze the angular dependence of the irreversible magnetization of YBa$_2$Cu$_3$O$_7$ crystals with columnar defects inclined from the c-axis. At high fields a sharp maximum centered at the tracks' direction is observed. At low fields we identify a lock-in phase characterized by an angle-independent pinning strength and observe an angular shift of the peak towards the c-axis that originates in the material anisotropy. The interplay among columnar defects, twins and ab-planes generates a variety of staircase structures. We show that correlated pinning dominates for all field orientations.

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A. Silhanek, L. Civale, S. Candia, G. Nieva, G. Pasquini, H. Lanza. 1999-02-22. Evidence for vortex staircases in the whole angular range due to competing correlated pinning mechanisms. https://doi.org/10.1103/physrevb.59.13620

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