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arXiv · 2412.17594

Simultaneous achievement of record-breaking colossal magnetoresistance and angular magnetoresistance in an antiferromagnetic semiconductor EuSe2

Qingxin Dong·Pengtao Yang·Zhihao Liu·Yuzhi Wang·Ziyi Liu·Tong Shi·Zhaoming Tian·Jianping Sun·Yoshiya Uwatoko·Quansheng Wu·Genfu Chen·Bosen Wang·Jinguang Cheng
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Abstract

Magnetoresistance effect lays the foundation for spintronics, magnetic sensors and hard drives. The pursuit of magnetic materials with colossal magnetoresistance (CMR) and/or angular magnetoresistance (AMR) has attracted enduring research interest and extensive investigations over past decades. Here we report on the discovery of field-induced record-breaking CMR of ~ -10^14 % and AMR ~ 10^14% achieved simultaneously in an antiferromagnetic rare-earth dichalcogenide EuSe2. Such intriguing observations are attributed to strong magnetic anisotropy and magnetic-field induced antiferromagnetic to ferromagnetic transition of the localized Eu2+ spins, which in turn closes the bandgap by lifting the degeneracy of Se-5p bands near Fermi level. Our DFT calculations perfectly replicate the experimental findings based on the Brillouin function and carries transport model. The present work provides a potential simple antiferromagnetic material for achieving angle-sensitive spintronic devices.

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Qingxin Dong, Pengtao Yang, Zhihao Liu, Yuzhi Wang, Ziyi Liu, Tong Shi, Zhaoming Tian, Jianping Sun, Yoshiya Uwatoko, Quansheng Wu, Genfu Chen, Bosen Wang, Jinguang Cheng. 2024-12-23. Simultaneous achievement of record-breaking colossal magnetoresistance and angular magnetoresistance in an antiferromagnetic semiconductor EuSe2. https://arxiv.org/abs/2412.17594

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