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arXiv · 2412.20531

Unraveling the temperature-dependent spin-polarized electron transport in iron via spin-wave Doppler shift

José Solano·Quentin Rossi·Jerome Robert·Marc Lenertz·Yves Henry·Benoit Gobaut·David Halley·Mattieu Bailleul
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Abstract

An electric current flowing in a ferromagnetic metal carries spin angular momentum, i.e. it is spin-polarized. Here, we measure the spin-wave Doppler shift induced by the transfer of angular momentum from the diffusive spin-polarized electric current onto coherent spin waves in epitaxial MgO/Fe/MgO thin films. We follow this Doppler shift as function of the temperature and determine that the degree of spin-polarization of the current increases from 77$\%$ to 86$\%$ when cooling the device from 303K down to 10K. Interpreting these measurements within the two-current model, we separate the contributions from electron-surface, electron-phonon and electron-magnon scatterings to the spin-dependent resistivity of Fe.

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José Solano, Quentin Rossi, Jerome Robert, Marc Lenertz, Yves Henry, Benoit Gobaut, David Halley, Mattieu Bailleul. 2024-12-29. Unraveling the temperature-dependent spin-polarized electron transport in iron via spin-wave Doppler shift. https://arxiv.org/abs/2412.20531

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