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DOE OSTI · 1851734

Electrical and optical characterizations of spin-orbit torque

Huang, Hanshen·Wu, Hao·Yu, Tian·Pan, Quanjun·Dai, Bingqian·Razavi, Armin·Wong, Kin·Cui, Baoshan·Chong, Su Kong·Wu, Di·Wang, Kang L.
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Abstract

To further reduce the energy consumption in spin–orbit torque devices, it is crucial to precisely quantify the spin–orbit torque (SOT) in different materials and structures. In this work, heavy metal/ferromagnet and heavy metal/ferrimagnet heterostructures are employed as the model systems to compare the electrical and optical methods for the SOT characterization, which are based on the anomalous Hall effect and the magneto-optical Kerr effect, respectively. It is found that both methods yield the consistent SOT strength for the current-driven magnetization switching measurements and the harmonic measurements. Our results suggest that the optical method is a feasible and reliable tool to investigate SOT, which is a powerful way to develop insulator-based magnetic systems in the future.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Huang, Hanshen, Wu, Hao, Yu, Tian, Pan, Quanjun, Dai, Bingqian, Razavi, Armin, Wong, Kin, Cui, Baoshan, Chong, Su Kong, Wu, Di, Wang, Kang L.. 2021-02-16. Electrical and optical characterizations of spin-orbit torque. https://doi.org/10.1063/5.0045091

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