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Ab-initio GMR and current-induced torques in Au/Cr multilayers

P. M. Haney·D. Waldron·R. A. Duine·A. S. Nunez·H. Guo·A. H. MacDonald
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Abstract

We report on an {\em ab-initio} study of giant magnetoresistance (GMR) and current-induced-torques (CITs) in Cr/Au multilayers that is based on non-equilibrium Green's functions and spin density functional theory. We find substantial GMR due primarily to a spin-dependent resonance centered at the Cr/Au interface and predict that the CITs are strong enough to switch the antiferromagnetic order parameter at current-densities $\sim 100$ times smaller than typical ferromagnetic metal circuit switching densities.

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P. M. Haney, D. Waldron, R. A. Duine, A. S. Nunez, H. Guo, A. H. MacDonald. 2006-11-23. Ab-initio GMR and current-induced torques in Au/Cr multilayers. https://doi.org/10.1103/physrevb.75.174428

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