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arXiv · 1208.4820

Vortex kinks in superconducting films with periodically modulated thickness

Jorge I. Facio·Anabella Abate·J. Guimpel·Pablo S. Cornaglia
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Abstract

We report magnetoresistance measurements through Nb films having a periodic thickness modulation. The cylinder shaped large-thickness regions of the sample, which form a square lattice, act as repulsive centers for the superconducting vortices. For low driving currents along one of the axes of the square lattice, the resistivity $ρ$ increases monotonously with increasing magnetic field $B$ and the $ρ$--$B$ characteristics are approximately piecewise linear. The linear $ρ$ vs $B$ segments change their slope at matching fields where the number of vortices is an integer or a half integer times the number of protruding cylinders in the sample. Numerical simulations allow us to associate the different segments of linear magnetoresistance to different vortex-flow regimes, some of which are dominated by the propagation of discommensurations (kinks).

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Jorge I. Facio, Anabella Abate, J. Guimpel, Pablo S. Cornaglia. 2013-03-27. Vortex kinks in superconducting films with periodically modulated thickness. https://doi.org/10.1088/0953-8984%2F25%2F24%2F245701

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