Direct determination of the spin-polarization at buried interfaces using voltage dependent MOKE signals

Michael Miller; Rene Nacke; Sven Ilse; Gisela Schütz; Eberhard Goering

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arXiv · 2308.06099

Direct determination of the spin-polarization at buried interfaces using voltage dependent MOKE signals

Michael Miller·Rene Nacke·Sven Ilse·Gisela Schütz·Eberhard Goering

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Abstract

Here, we report a novel and conceptually straightforward technique to detect the spin-polarization directly, with laser spot spatial resolution, at buried ferromagnet/insulator interfaces in ambient settings. This has been accomplished by monitoring the voltage-induced change of the longitudinal MOKE signal as a function of the applied magnetic field and applying an AC voltage across the interface. For the case where the spin polarization enters the VMOKE signal, a simple quantitative model is proposed. A distinct positive majority spin polarization has been found for Fe and Co, whereas Ni exhibits a negative minority spin polarization.

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Michael Miller, Rene Nacke, Sven Ilse, Gisela Schütz, Eberhard Goering. 2024-02-13. Direct determination of the spin-polarization at buried interfaces using voltage dependent MOKE signals. https://arxiv.org/abs/2308.06099

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