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arXiv · 1310.6165

Unusual magneto-transport of YBa2Cu3O7-d films due to the interplay of anisotropy, random disorder and nanoscale periodic pinning

J. Trastoy·V. Rouco·C. Ulysse·R. Bernard·A. Palau·T. Puig·G. Faini·J. Lesueur·J. Briatico·J. E. Villegas
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Abstract

We study the general problem of a manifold of interacting elastic lines whose spatial correlations are strongly affected by the competition between random and ordered pinning. This is done through magneto-transport experiments with YBa2Cu3O7-d thin films that contain a periodic vortex pinning array created via masked ion irradiation, in addition to the native random pinning. The strong field-matching effects we observe suggest the prevalence of periodic pinning, and indicate that at the matching field each vortex line is bound to an artificial pinning site. However, the vortex-glass transition dimensionality, quasi-2D instead of the usual 3D, evidences reduced vortex-glass correlations along the vortex line. This is also supported by an unusual angular dependence of the magneto-resistance, which greatly differs from that of Bose-glass systems. A quantitative analysis of the angular magnetoresistance allows us to link this behaviour to the enhancement of the system anisotropy, a collateral effect of the ion irradiation.

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J. Trastoy, V. Rouco, C. Ulysse, R. Bernard, A. Palau, T. Puig, G. Faini, J. Lesueur, J. Briatico, J. E. Villegas. 2013-10-23. Unusual magneto-transport of YBa2Cu3O7-d films due to the interplay of anisotropy, random disorder and nanoscale periodic pinning. https://doi.org/10.1088/1367-2630%2F15%2F10%2F103022

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