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Tunable magnetization damping in transition metal ternary alloys

S. Ingvarsson·Gang Xiao·S. S. P. Parkin·R. H. Koch
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Abstract

We show that magnetization damping in Permalloy, Ni80Fe20 (``Py''), can be enhanced sufficiently to reduce post-switching magnetization precession to an acceptable level by alloying with the transition metal osmium (Os). The damping increases monotonically upon raising the Os-concentration in Py, at least up to 9% of Os. Other effects of alloying with Os are suppression of magnetization and enhancement of in-plane anisotropy. Magnetization damping also increases significantly upon alloying with the five other transition metals included in this study (4d-elements: Nb, Ru, Rh; 5d-elements: Ta, Pt) but never as strongly as with Os.

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S. Ingvarsson, Gang Xiao, S. S. P. Parkin, R. H. Koch. 2004-08-27. Tunable magnetization damping in transition metal ternary alloys. https://doi.org/10.1063/1.1828232

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