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Dipole-induced vortex ratchets in superconducting films with arrays of micromagnets

C. C. de Souza Silva·A. V. Silhanek·J. Van de Vondel·W. Gillijns·V. Metlushko·B. Ilic·V. V. Moshchalkov
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Abstract

We investigate the transport properties of superconducting films with periodic arrays of in-plane magnetized micromagnets. Two different magnetic textures are studied: a square array of magnetic bars and a close-packed array of triangular microrings. As confirmed by MFM imaging, the magnetic state of both systems can be adjusted to produce arrays of almost point-like magnetic dipoles. By carrying out transport measurements with ac drive, we observed experimentally a recently predicted ratchet effect induced by the interaction between superconducting vortices and the magnetic dipoles. Moreover, we find that these magnetic textures produce vortex-antivortex patterns, which have a crucial role on the transport properties of this hybrid system.

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C. C. de Souza Silva, A. V. Silhanek, J. Van de Vondel, W. Gillijns, V. Metlushko, B. Ilic, V. V. Moshchalkov. 2007-01-18. Dipole-induced vortex ratchets in superconducting films with arrays of micromagnets. https://doi.org/10.1103/physrevlett.98.117005

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