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Flux-flow induced giant magnetoresistance in all-amorphous superconductor-ferromagnet hybrids

C. Bell·S. Tursucu·J. Aarts
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Abstract

We present magnetoresistance measurements on all-amorphous ferromagnet (F) / superconductor (S) heterostructures. The F/S/F trilayers show large magnetoresistance peaks in a small field range around the coercive field of the F layers, at temperatures within and below the superconducting transition. This is interpreted as flux flow of weakly pinned vortices induced by the stray field of Bloch magnetic domains in the F layers. Bilayers show much smaller effects, implying that the Bloch walls of the F-layers in the trilayer line up and focus the stray fields. The data are used to discuss the expected minimum F-layer thickness needed to nucleate vortices.

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C. Bell, S. Tursucu, J. Aarts. 2006-10-24. Flux-flow induced giant magnetoresistance in all-amorphous superconductor-ferromagnet hybrids. https://doi.org/10.1103/physrevb.74.214520

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