Universal orbital and magnetic structures in infinite-layer nickelates

M. Rossi; H. Lu; K. Lee; B. H. Goodge; J. Choi; M. Osada; Y. Lee; D. Li; B. Y. Wang; D. Jost; S. Agrestini; M. Garcia-Fernandez; Z. X. Shen; Ke-Jin Zhou; E. Been; B. Moritz; L. F. Kourkoutis; T. P. Devereaux; H. Y. Hwang; W. S. Lee

arXiv · 2312.16444

Universal orbital and magnetic structures in infinite-layer nickelates

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Abstract

We conducted a comparative study of the rare-earth infinite-layer nickelates films, RNiO2 (R = La, Pr, and Nd) using resonant inelastic X-ray scattering (RIXS). We found that the gross features of the orbital configurations are essentially the same, with minor variations in the detailed hybridization. For low-energy excitations, we unambiguously confirm the presence of damped magnetic excitations in all three compounds. By fitting to a linear spin-wave theory, comparable spin exchange coupling strengths and damping coefficients are extracted, indicating a universal magnetic structure in the infinite-layer nickelates. Interestingly, while signatures of a charge order are observed in LaNiO2 in the quasi-elastic region of the RIXS spectrum, it is absent in NdNiO2 and PrNiO2. This prompts further investigation into the universality and the origins of charge order within the infinite-layer inickelates.

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M. Rossi, H. Lu, K. Lee, B. H. Goodge, J. Choi, M. Osada, Y. Lee, D. Li, B. Y. Wang, D. Jost, S. Agrestini, M. Garcia-Fernandez, Z. X. Shen, Ke-Jin Zhou, E. Been, B. Moritz, L. F. Kourkoutis, T. P. Devereaux, H. Y. Hwang, W. S. Lee. 2023-12-27. Universal orbital and magnetic structures in infinite-layer nickelates. https://arxiv.org/abs/2312.16444

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