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Half-metallic ferromagnets for magnetic tunnel junctions

Phivos Mavropoulos·Marjana Lezaic·Stefan Bluegel
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Abstract

Using theoretical arguments, we show that, in order to exploit half-metallic ferromagnets in tunneling magnetoresistance (TMR) junctions, it is crucial to eliminate interface states at the Fermi level within the half-metallic gap; contrary to this, no such problem arises in giant magnetoresistance elements. Moreover, based on an a priori understanding of the electronic structure, we propose an antiferromagnetically coupled TMR element, in which interface states are eliminated, as a paradigm of materials design from first principles. Our conclusions are supported by ab-initio calculations.

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Phivos Mavropoulos, Marjana Lezaic, Stefan Bluegel. 2005-06-03. Half-metallic ferromagnets for magnetic tunnel junctions. https://doi.org/10.1103/physrevb.72.174428

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