Vortex kinks in superconducting films with periodically modulated thickness
Abstract
We report magnetoresistance measurements in Nb films having a periodic thickness modulation. The cylinder shaped thicker 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 versus 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).
- Publication:
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Journal of Physics Condensed Matter
- Pub Date:
- June 2013
- DOI:
- 10.1088/0953-8984/25/24/245701
- arXiv:
- arXiv:1208.4820
- Bibcode:
- 2013JPCM...25x5701F
- Keywords:
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- Condensed Matter - Superconductivity
- E-Print:
- Journal of Physics Condensed Matter 2013