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arXiv · 0712.0308

Current reversal in collective ratchets induced by lattice instability

L. Dinis·E. M. Gonzalez·J. V. Anguita·J. M. R. Parrondo·J. L. Vicent
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Abstract

A collective mechanism for current reversal in superconducting vortex ratchets is proposed. The mechanism is based on a two-dimensional instability of the ground state (T=0) of the system. We illustrate our results with numerical simulations and experiments in Nb superconducting films fabricated on top of Si substrates with artificially induced asymmetric pinning centers.

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L. Dinis, E. M. Gonzalez, J. V. Anguita, J. M. R. Parrondo, J. L. Vicent. 2007-12-03. Current reversal in collective ratchets induced by lattice instability. https://doi.org/10.1103/physrevb.76.212507

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