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arXiv · 1910.05247

Magnetization governed magnetoresistance anisotropy in topological semimetal CeBi

Yang-Yang Lyu·Fei Han·Zhi-Li Xiao·Jing Xu·Yong-Lei Wang·Hua-Bing Wang·Jin-Ke Bao·Duck Young Chung·Mingda Li·Ivar Martin·Ulrich Welp·Mercouri G. Kanatzidis·Wai-Kwong Kwok
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Abstract

Magnetic topological semimetals, the latest member of topological quantum materials, are attracting extensive attention as they may lead to topologically-driven spintronics. Currently, magnetotransport investigations on these materials are focused on anomalous Hall effect. Here, we report on the magnetoresistance anisotropy of topological semimetal CeBi, which has tunable magnetic structures arising from localized Ce 4f electrons and exhibits both negative and positive magnetoresistances, depending on the temperature. We found that the angle dependence of the negative magnetoresistance, regardless of its large variation with the magnitude of the magnetic field and with temperature, is solely dictated by the field-induced magnetization that is orientated along a primary crystalline axis and flops under the influence of a rotating magnetic field. The results reveal the strong interaction between conduction electrons and magnetization in CeBi. They also indicate that magnetoresistance anisotropy can be used to uncover the magnetic behavior and the correlation between transport phenomena and magnetism in magnetic topological semimetals.

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Yang-Yang Lyu, Fei Han, Zhi-Li Xiao, Jing Xu, Yong-Lei Wang, Hua-Bing Wang, Jin-Ke Bao, Duck Young Chung, Mingda Li, Ivar Martin, Ulrich Welp, Mercouri G. Kanatzidis, Wai-Kwong Kwok. 2019-10-11. Magnetization governed magnetoresistance anisotropy in topological semimetal CeBi. https://doi.org/10.1103/physrevb.100.180407

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