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arXiv · 1902.04665

Effective field analysis using the full angular spin-orbit torque magnetometry dependence

Abstract

Spin-orbit torques promise ultra-efficient magnetization switching used for advanced devices based on emergent quasi-particles such as domain walls and skyrmions. Recently, the spin structure dynamics, materials and systems with tailored spin-orbit torques are being developed. A method, which allows one to detect the acting torques in a given system as a function of the magnetization direction is the torque-magnetometry method based on a higher harmonics analysis of the anomalous Hall-effect. Here we show that the effective fields acting on magnetic domain walls that govern the efficiency of their dynamics require a sophisticated analysis taking into account the full angular dependence of the torques. Using a 1-D model we compared the spin orbit torque efficiencies by depinning measurements and spin torque magnetometry. We show that the effective fields can be accurately determined and we find good agreement. Thus our method allows us now to rapidly screen materials and predict the resulting quasi-particle dynamics.

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Tomek Schulz, Kyujoon Lee, Benjamin Krüger, Roberto Lo Conte, Gurucharan V. Karnad, Karin Garcia, Laurent Vila, Berthold Ocker, Dafiné Ravelosona, Mathias Kläui. 2019-02-12. Effective field analysis using the full angular spin-orbit torque magnetometry dependence. https://doi.org/10.1103/physrevb.95.224409

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