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arXiv · 1112.2110

Spin polarized tunneling in MgO-based tunnel junctions with superconducting electrodes

Oliver Schebaum·Jagadeesh S. Moodera·Andy Thomas
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Abstract

We prepared magnetic tunnel junctions with one ferromagnetic and one superconducting Al-Si electrode. Pure cobalt electrodes were compared with a Co-Fe-B alloy and the Heusler compound Co2FeAl. The polarization of the tunneling electrons was determined using the Maki-Fulde-model and is discussed along with the spin-orbit scattering and the total pair-breaking parameters. The junctions were post-annealed at different temperatures to investigate the symmetry filtering mechanism responsible for the giant tunneling magnetoresistance ratios in Co-Fe-B/ MgO/ Co-Fe-B junctions.

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Oliver Schebaum, Jagadeesh S. Moodera, Andy Thomas. 2011-12-09. Spin polarized tunneling in MgO-based tunnel junctions with superconducting electrodes. https://doi.org/10.1088/1367-2630%2F14%2F3%2F033023

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