Core-level x-ray photoemission and Raman spectroscopy studies on electronic structures in Mott-Hubbard type nickelate oxide NdNiO$_2$

Ying Fu; Le Wang; Hu Cheng; Shenghai Pei; Xuefeng Zhou; Jian Chen; Shaoheng Wang; Ran Zhao; Wenrui Jiang; Cai Liu; Mingyuan Huang; XinWei Wang; Yusheng Zhao; Dapeng Yu; Fei Ye; Shanmin Wang; Jia-Wei Mei

arXiv · 1911.03177

Core-level x-ray photoemission and Raman spectroscopy studies on electronic structures in Mott-Hubbard type nickelate oxide NdNiO$_2$

Ying Fu·Le Wang·Hu Cheng·Shenghai Pei·Xuefeng Zhou·Jian Chen·Shaoheng Wang·Ran Zhao·Wenrui Jiang·Cai Liu·Mingyuan Huang·XinWei Wang·Yusheng Zhao·Dapeng Yu·Fei Ye·Shanmin Wang·Jia-Wei Mei

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Abstract

We perform core-level X-ray photoemission spectroscopy (XPS) and electronic Raman scattering studies of electronic structures and spin fluctuations in the bulk samples of the nickelate oxide NdNiO$_2$. According to Nd $3d$ and O $1s$ XPS spectra, we conclude that NdNiO$_2$ has a large transfer energy. From the analysis of the main line of the Ni $2p_{3/2}$ XPS, we confirm the NiO$_2$ planes in NdNiO$_2$ are of Mott-Hubbard type in the Zaanen-Sawatzky-Allen scheme. The two-magnon peak in the Raman scattering provides direct evidence for the strong spin-fluctuation in NdNiO$_2$. The peak position determines the antiferromagnetic exchange $J=25$~meV. Our experimental results agree well with our previous theoretical results.

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Ying Fu, Le Wang, Hu Cheng, Shenghai Pei, Xuefeng Zhou, Jian Chen, Shaoheng Wang, Ran Zhao, Wenrui Jiang, Cai Liu, Mingyuan Huang, XinWei Wang, Yusheng Zhao, Dapeng Yu, Fei Ye, Shanmin Wang, Jia-Wei Mei. 2019-11-08. Core-level x-ray photoemission and Raman spectroscopy studies on electronic structures in Mott-Hubbard type nickelate oxide NdNiO$_2$. https://arxiv.org/abs/1911.03177

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