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Magnetoresistive Effects in Ferromagnet-Superconductor Multilayers

E. M. Stoudenmire·C. A. R. Sá de Melo
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Abstract

We consider a nanoscale system consisting of Manganite-ferromagnet and Cuprate-superconductor multilayers in a spin valve configuration. The magnetization of the bottom Manganite-ferromagnet is pinned by a Manganite-antiferromagnet. The magnetization of the top Manganite-ferromagnet is coupled to the bottom one via indirect exchange through the superconducting layers. We study the behavior of the critical temperature and the magnetoresistance as a function of an externally applied parallel magnetic field, when the number of Cuprate-superconductor layers are changed. There are two typical behaviors in the case of a few monolayers of the Cuprates: a) For small magnetic fields, the critical temperature and the magnetoresistance change abruptly when the flipping field of the top Manganite-ferromagnet is reached. b) For large magnetic fields, the multilayered system re-enters the zero-resistance (superconducting) state after having become resistive (normal).

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E. M. Stoudenmire, C. A. R. Sá de Melo. 2004-12-01. Magnetoresistive Effects in Ferromagnet-Superconductor Multilayers. https://doi.org/10.1063/1.1850411

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