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arXiv · 2412.09003

Evolution of magnetism in Ruddlesden-Popper bilayer nickelate revealed by muon spin relaxation

K. W. Chen·X. Q. Liu·Y. Wang·Z. Y. Zhu·J. C. Jiao·C. Y. Jiang·Y. F. Guo·L. Shu
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Abstract

Here we report the positive muon spin relaxation study on Pr-doped La$_{1.9}$Pr$_{1.1}$Ni$_2$O$_{6.97}$ and oxygen-deficient La$_3$Ni$_2$O$_{6.63}$ polycrystalline under ambient pressure. Zero-field $\mu^+$SR experiments reveal the existence of bulk long-range magnetic order in La$_{1.9}$Pr$_{1.1}$Ni$_2$O$_{6.97}$ with $T_{N}=161\ \rm{K}$, while La$_3$Ni$_2$O$_{6.63}$ exhibits a short-range magnetic ground state with $T_N=30\ \rm{K}$. The magnetic transition width of La$_{1.9}$Pr$_{1.1}$Ni$_2$O$_{6.97}$ revealed by weak-transverse-field $\mu^+$SR is narrower compared to La$_3$Ni$_2$O$_{6.92}$. Our $\mu^+$SR experiment results provide a comprehensive view on the correlation between magnetism and structure perfection in Ruddlesden-Popper bilayer nickelates under ambient pressure.

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K. W. Chen, X. Q. Liu, Y. Wang, Z. Y. Zhu, J. C. Jiao, C. Y. Jiang, Y. F. Guo, L. Shu. 2024-12-12. Evolution of magnetism in Ruddlesden-Popper bilayer nickelate revealed by muon spin relaxation. https://arxiv.org/abs/2412.09003

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