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arXiv · 1404.5030

Robust antiferromagnetism preventing superconductivity in pressurized Ba0.61K0.39Mn2Bi2

Abstract

Here, we report that K-doped BaMn2Bi2 shows no experimental evidence of superconductivity down to 1.5 K under pressures up to 35.6 GPa, however, a tetragonal to an orthorhombic phase transition is observed at pressure of 20 GPa. Theoretical calculations for the tetragonal and orthorhombic phases, on basis of our high-pressure XRD data, find that the AFM order is robust in both of the phases in pressurized Ba0.61K0.39Mn2Bi2. Our experimental and theoretical results suggest that the K-doped BaMn2Bi2 belongs to a strong Hunds AFM metal with a hybridization of localized spin electrons and itinerant electrons, and that its robust AFM order essentially prevents the emergence of superconductivity.

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Dachun Gu, Xia Dai, Congcong Le, Liling Sun, Qi Wu, Bayrammurad Saparov, Jing Guo, Peiwen Gao, Shan Zhang, Yazhou Zhou, Chao Zhang, Lun Xiong, Rui Li, Yanchun Li, Xiaodong Li, Jing Liu, Athena S. Sefat, Jiangping Hu, Zhongxian Zhao. 2014-04-20. Robust antiferromagnetism preventing superconductivity in pressurized Ba0.61K0.39Mn2Bi2. https://arxiv.org/abs/1404.5030

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