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arXiv · 1004.4631

Andreev reflection in ferrimagnetic CoFe2O4/SrRuO3 spin filters

Franco Rigato·Samanta Piano·Michael Foerster·Filippo Giubileo·Anna Maria Cucolo·Josep Fontcuberta
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Abstract

We have performed point contact spectroscopy measurements on a sample constituted by a metallic ferromagnetic oxide (SrRuO_3) bottom electrode and a tunnel ferrimagnetic (CoFe_2O_4) barrier. Andreev reflection is observed across the tunnel barrier. From the comparison of Andreev reflection in SrRuO3 and across the CoFe_2O_4 barrier we infer that the ferrimagnetic barrier has a spin filter efficiency not larger than +13%. The observation of a moderate and positive spin filtering is discussed in the context of the microstructure of the barriers and symmetry-related spin filtering effects.

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Franco Rigato, Samanta Piano, Michael Foerster, Filippo Giubileo, Anna Maria Cucolo, Josep Fontcuberta. 2010-04-26. Andreev reflection in ferrimagnetic CoFe2O4/SrRuO3 spin filters. https://doi.org/10.1103/physrevb.81.174415

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