We report the synthesis and characterization of a rare-earth dichalcogenide EuTe2. An antiferromagnetic transition was found at TM = 11 K. The antiferromagnetic order can be tuned by an applied magnetic field to access a first-order spin flop transition and a spin flip transition. These transitions are associated with a giant negative magnetoresistance with a value of nearly 100\%. Heat capacity measurements reveal strong electronic correlations and a reduced magnetic entropy. Furthermore, density functional theory calculations demonstrate that the electrons near the Fermi surface mainly originate from the Te 5p orbitals and the magnetism is dominated by localized electrons from the Eu 4f orbitals. These results suggest that both the RKKY and Kondo interactions between the local moments and itinerant electrons play crucial roles in the magnetism and large negative magnetoresistance of EuTe2.
@article{arxiv.1909.08340,
title = {Large negative magnetoresistance in the new antiferromagnetic rare-earth dichalcogenide EuTe$_2$},
author = {Junjie Yin and Changwei Wu and Lisi Li and Jia Yu and Hualei Sun and Bing Shen and Benjamin A. Frandsen and Dao-Xin Yao and Meng Wang},
journal= {arXiv preprint arXiv:1909.08340},
year = {2020}
}