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Systematic Two-band Model Calculations of the GMR Effect with Metallic and Nonmetallic Spacers and with Impurities

O. Gebele·M. Böhm·U. Krey·S. Krompiewski
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Abstract

By an accurate Green's function method we calculate conductances and the corresponding Giant Magneto-Resistance effects (GMR) of two metallic ferromagnetic films separated by different spacers, metallic and non-metallic ones, in a simplified model on a sc lattice, in CPP and CIP geometries (i.e. current perpendicular or parallel to the planes), without impurities, or with interface- or bulk impurities. The electronic structure of the systems is approximated by two hybridized orbitals per atom, to mimic s-bands and d-bands and their hybridization. We show that such calculations usually give rough estimates only, but of the correct order of magnitude; in particular, the predictions on the impurity effects depend strongly on the model parameters. One of our main results is the prediction of huge CPP-GMR effects for {\it non-metallic} spacers in the ballistic limit.

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O. Gebele, M. Böhm, U. Krey, S. Krompiewski. 2000-03-02. Systematic Two-band Model Calculations of the GMR Effect with Metallic and Nonmetallic Spacers and with Impurities. https://doi.org/10.1016/s0304-8853(00)00145-1

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