发表机构
Harvard University; Brookhaven National Laboratory; Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory; European Synchrotron Radiation Facility; Argonne National Laboratory（哈佛大学; 布鲁克海文国家实验室; SLAC国家加速器实验室斯坦福材料与能源科学研究所; 欧洲同步辐射装置; 阿贡国家实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过XAS和RIXS解析三层镍酸盐Pr$_4$Ni$_3$O$_{10}$的多轨道电子结构与磁激发，发现多层架构是调控磁相互作用的关键，而非稀土取代。
AI 中文摘要
稀土取代显著改变了Ruddlesden-Popper（RP）镍酸盐的结构、金属性和超导行为，但其对磁相互作用的影响仍不清楚。本文结合X射线吸收谱（XAS）和共振非弹性X射线散射（RIXS）来解析Pr$_4$Ni$_3$O$_{10}$的多轨道电子结构和磁激发。稀土共振吸收的缺失为直接探测Ni $L_3$边提供了条件，而Ni $L$边和O $K$边的偏振相关测量则分辨出不同的面内和面外Ni-O杂化通道。动量分辨的RIXS揭示了色散的磁激发，这些激发在接近不相称自旋密度波波矢时变软。有效的自旋波分析得出显著的层内三层层间交换耦合，其大小与主要的面内相互作用相当，并且对稀土取代具有鲁棒性。我们的结果确定了多层架构，而非单独的稀土取代，是这些材料中磁相互作用的关键调控手段。
英文摘要
Rare-earth substitution strongly modifies the structure, metallicity, and superconducting behavior of Ruddlesden-Popper (RP) nickelates, but its impact on their magnetic interactions remains unclear. Here, we combine x-ray absorption spectroscopy (XAS) and resonant inelastic x-ray scattering (RIXS) to resolve the multiorbital electronic structure and magnetic excitations of Pr$_4$Ni$_3$O$_{10}$. The absence of an overlapping rare-earth resonance provides direct access to the Ni $L_3$ edge, while polarization-dependent measurements at the Ni $L$- and O $K$-edges resolve distinct planar and out-of-plane Ni-O hybridization channels. Momentum-resolved RIXS reveals dispersive magnetic excitations that soften toward the incommensurate spin-density-wave wave vector. An effective spin-wave analysis yields a sizable intra-trilayer exchange coupling, comparable to the leading in-plane interactions and robust against rare-earth substitution. Our results identify the multilayer architecture, rather than rare-earth substitution alone, as a key control knob of the magnetic interactions in these materials.
CommentsMain: 9 pages, 4 figures; Supplementary: 25 pages, 23 figures
