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arXiv · 1211.3311

Anisotropy and directional pinning in YBaCuO with BaZrO3 nanorods

N. Pompeo·A. Augieri·K. Torokhtii·V. Galluzzi·G. Celentano·E. Silva
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Abstract

Measurements of anisotropic transport properties (dc and high-frequency regime) of driven vortex matter in YBa$_2$Cu$_3$O$_{7-x}$ with elongated strong-pinning sites (c-axis aligned, self-assembled BaZrO$_3$ nanorods) are used to demonstrate that the effective-mass angular scaling takes place only in intrinsic physical quantities (flux-flow resistivity), and not in pinning-related Labusch parameter and critical currents. Comparison of the dynamics at different time scales shows evidence for a transition of the vortex matter toward a Mott phase, driven by the presence of nanorods. The strong pinning in dc arises partially from a dynamic effect.

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N. Pompeo, A. Augieri, K. Torokhtii, V. Galluzzi, G. Celentano, E. Silva. 2013-06-24. Anisotropy and directional pinning in YBaCuO with BaZrO3 nanorods. https://doi.org/10.1063/1.4813405

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