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Anomalous magnetoresistance behavior of CoFe nano-oxide spin valves at low temperatures

J. Ventura·J. B. Sousa·M. A. Salgueiro da Silva·P. P. Freitas·A. Veloso
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Abstract

We report magnetoresistance curves of CoFe nano-oxide specular spin valves of MnIr/CoFe/nano-oxidized CoFe/CoFe/Cu/CoFe/nano-oxidized CoFe/Ta at different temperatures from 300 to 20 K. We extend the Stoner-Wolfarth model of a common spin valve to a specular spin valve, introducing the separation of the pinned layer into two sublayers and their magnetic coupling across the nano-oxide. We study the effect of different coupling/exchange (between the antiferromagnetic layer and the bottom sublayer) field ratios on the magnetization and magnetoresistance, corresponding with the experimentally observed anomalous bumps in low temperature magnetoresistance curves.

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J. Ventura, J. B. Sousa, M. A. Salgueiro da Silva, P. P. Freitas, A. Veloso. 2005-07-18. Anomalous magnetoresistance behavior of CoFe nano-oxide spin valves at low temperatures. https://doi.org/10.1063/1.1540149

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