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arXiv · 1304.2763

Paramagnetic Fe_xTa_{1-x} alloys for engineering of perpendicularly magnetized tunnel junctions

Matthias Gottwald·Jimmy J. Kan·Kangho Lee·Seung H. Kang·Eric E. Fullerton
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Abstract

Exchange coupling between two magnetic layers through an interlayer is of broad interest for numerous recent applications of nano-magnetic systems. In this Letter we study ferromagnetic exchange coupling through amorphous paramagnetic Fe-Ta alloys. We show that the exchange coupling depends exponentially on spacer thickness and scales with the Fe-Ta susceptibility, which can be tuned via the alloy composition and/or temperature. Such materials are of high interest for the engineering of perpendicularly magnetized CoFeB-MgO based tunnel junctions as it enables ferromagnetic coupling of magnetic layers with differing crystalline lattices, suppresses dead layers and can act as an inter-diffusion barrier during annealing.

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Matthias Gottwald, Jimmy J. Kan, Kangho Lee, Seung H. Kang, Eric E. Fullerton. 2013-04-09. Paramagnetic Fe_xTa_{1-x} alloys for engineering of perpendicularly magnetized tunnel junctions. https://arxiv.org/abs/1304.2763

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