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arXiv · 2405.14460

Detecting slow magnetization relaxation via magnetotransport measurements based on the current-reversal method

Abstract

Slow magnetization relaxation processes are an important time-dependent property of many magnetic materials. We show that magnetotransport measurements based on a well-established current-reversal method can be utilized to implement a simple and robust screening scheme for such relaxation processes. We demonstrate our approach considering the anomalous Hall effect in a Pt/Co/AlOx trilayer model system, and then explore relaxation in τ -MnAl films. Compared to magnetotransport experiments based on ac lock-in techniques, we find that the dc current-reversal method is particulary sensitive to relaxation processes with relaxation time scales on the order of seconds, comparable to the current-reversal measurement time scales.

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Sebastian Beckert, Richard Schlitz, Gregor Skobjin, Antonin Badura, Miina Leiviskä, Dominik Kriegner, Daniel Scheffler, Giacomo Sala, Kamil Olejník, Lisa Michez, Vincent Baltz, Andy Thomas, Helena Reichlová, Sebastian T. B. Goennenwein. 2024-05-23. Detecting slow magnetization relaxation via magnetotransport measurements based on the current-reversal method. https://arxiv.org/abs/2405.14460

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