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arXiv · 1712.03810

Spin-orbit torque magnetometry by wide-field magneto-optical Kerr effect

Tsung-Yu Tsai·Tian-Yue Chen·Chun-Ting Wu·Hsin-I Chan·Chi-Feng Pai
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Abstract

Magneto-optical Kerr effect (MOKE) is an efficient approach to probe surface magnetization in thin film samples. Here we present a wide-field MOKE technique that adopts a K$\"o$hler illumination scheme to characterize the current-induced damping-like spin-orbit torque (DL-SOT) in micronsized and unpatterned magnetic heterostructures with perpendicular magnetic anisotropy. Through a current-induced hysteresis loop shift analysis, we quantify the DL-SOT efficiency of a Ta-based heterostructure with bar-shaped geometry, Hall-cross geometry, and unpatterned geometry to be $|\xi_{DL}|\approx$ 0.08. The proposed wide-field MOKE approach therefore provides an instant and direct characterization of DL-SOT, without the need of any further interpretation on electrical signals.

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Tsung-Yu Tsai, Tian-Yue Chen, Chun-Ting Wu, Hsin-I Chan, Chi-Feng Pai. 2017-12-11. Spin-orbit torque magnetometry by wide-field magneto-optical Kerr effect. https://doi.org/10.1038/s41598-018-23951-w

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