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arXiv · 1612.05556

Relaxation mechanism driven by spin angular momentum absorption throughout antiferromagnetic phase transition in NiFe surface oxides

L. Frangou·G. Forestier·S. Auffret·S. Gambarelli·V. Baltz
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Abstract

We report an alternative mechanism for the physical origin of the temperature-dependent ferromagnetic relaxation of Permalloy (NiFe) thin films. Through spin-pumping experiments, we demonstrate that the peak in the temperature-dependence of NiFe damping can be understood in terms of enhanced spin angular momentum absorption at the magnetic phase transition in antiferromagnetic surface-oxidized layers. These results suggest new avenues for the investigation of an incompletely-understood phenomenon in physics.

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L. Frangou, G. Forestier, S. Auffret, S. Gambarelli, V. Baltz. 2016-12-16. Relaxation mechanism driven by spin angular momentum absorption throughout antiferromagnetic phase transition in NiFe surface oxides. https://doi.org/10.1103/physrevb.95.054416

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