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arXiv · 2311.15717

Evidence of spin density waves in La$_3$Ni$_2$O$_{7-δ}$

Kaiwen Chen·Xiangqi Liu·Jiachen Jiao·Muyuan Zou·Yixuan Luo·Qiong Wu·Ningyuan Zhang·Yanfeng Guo·Lei Shu
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Abstract

The recently discovered superconductivity with critical temperature $T_c$ up to 80 K in the double-layer Nickelate La$_3$Ni$_2$O$_{7-δ}$ under pressure has drawn great attention. Here we report the positive muon spin relaxation ($μ^+$SR) study of polycrystalline La$_3$Ni$_2$O$_{6.92}$ under ambient pressure. Zero-field $μ^+$SR experiments reveal the existence of magnetic order in La$_3$Ni$_2$O$_{6.92}$ with $T_{N}=154\ \rm{K}$. The weak transverse field $μ^+$SR measurements confirms the bulk nature of magnetism. In addition, a small quantity of oxygen deficiencies can greatly broaden the internal magnetic field distribution sensed by muons.

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Kaiwen Chen, Xiangqi Liu, Jiachen Jiao, Muyuan Zou, Yixuan Luo, Qiong Wu, Ningyuan Zhang, Yanfeng Guo, Lei Shu. 2024-05-13. Evidence of spin density waves in La$_3$Ni$_2$O$_{7-δ}$. https://arxiv.org/abs/2311.15717

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