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arXiv · 2402.15741

Observation of the In-plane Anomalous Hall Effect induced by Octupole in Magnetization Space

Wenzhi Peng·Zheng Liu·Haolin Pan·Peng Wang·Yulong Chen·Jiachen Zhang·Xuhao Yu·Jinhui Shen·Mingmin Yang·Qian Niu·Yang Gao·Dazhi Hou
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Abstract

The Anomalous Hall Effect (AHE) manifests as a transverse voltage proportional to magnetization in ferromagnetic materials under the application of a charge current, being an indispensable tool for probing magnetism, especially in nanoscale devices. However, the AHE primarily sensitizes to out-of-plane magnetization, thereby hindering its capacity to discern the in-plane magnetization, a characteristic prevalent in ferromagnetic films. Here we challenge this conventional understanding by demonstrating the in-plane magnetization-induced AHE in iron and nickel, two ubiquitous ferromagnets. This observation of the in-plane AHE is remarkable as it contradicts existing theories that forbid such phenomena in cubic crystal systems. We trace the origin of this unanticipated phenomenon to a hitherto unconsidered octupole of the anomalous Hall conductivity in the magnetization space, a mechanism we propose could enable the detection of in-plane AHE in a wide range of ferromagnetic materials. This work realizes the in-plane AHE in common ferromagnets by exploiting the anomalous Hall conductivity octupole, revealing a new physical origin of the AHE and promising to revolutionize the design of magnetic devices and sensors.

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Wenzhi Peng, Zheng Liu, Haolin Pan, Peng Wang, Yulong Chen, Jiachen Zhang, Xuhao Yu, Jinhui Shen, Mingmin Yang, Qian Niu, Yang Gao, Dazhi Hou. 2024-02-24. Observation of the In-plane Anomalous Hall Effect induced by Octupole in Magnetization Space. https://doi.org/10.1088/0256-307x%2F43%2F6%2F060704

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