Spin and orbital excitations in undoped infinite-layer superconducting PrNiO2 and insulating CaCuO2
Artikel i vetenskaplig tidskrift, 2026
Infinite-layer nickelates are among the most promising cuprate-akin superconductors, although relevant differences from copper oxides have been reported. Here, we present momentum- and polarization-resolved RIXS measurements on nominally undoped, superconducting PrNiO2 , and compare its magnetic and orbital excitations with those of the reference infinite layer cuprate CaCuO2 . In PrNiO2 , the in-plane magnetic exchange integrals are smaller than in CaCuO2 , whereas the out-of-plane values are similar, indicating that both materials support three-dimensional antiferromagnetic correlations. Orbital excitations, associated to the transitions within 3d states of the metal, are well reproduced within a single-ion model and display similar characteristics, except the Ni-dxy peak that, besides lying at significantly lower energy, shows an opposite dispersion to that of Cu-dxy . We attribute this difference to the values of the orbital superexchange coupling between nearest neighbor sites. Our observations suggest that infinite-layer cuprates and nickelates share most of the spin and orbital properties, but in nickelates the larger charge-transfer energy Δ and smaller hopping integrals imply smaller spin-fluctuation energy and stronger localization of the doping charge on the metal site. https://doi.org/10.15151/ESRF-ES-1430231833.
Författare
Francesco Rosa
Universität zu Köln
Politecnico di Milano
H. Sahib
IPCMS Institut de Physique et Chimie des Materiaux de Strasbourg
University of Halabja
Giacomo Merzoni
Politecnico di Milano
European XFEL
L. Martinelli
Universität Zürich
Politecnico di Milano
Riccardo Arpaia
Universita Ca' Foscari Venezia
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Nicholas B. Brookes
European Synchrotron Radiation Facility (ESRF)
D. Di Castro
Universita degli Studi di Roma Tor Vergata
K. Wohlfeld
Uniwersytet Warszawski
Maryia Zinouyeva
Politecnico di Milano
Marco Salluzzo
Consiglio Nazionale delle Ricerche (CNR)
D. Preziosi
IPCMS Institut de Physique et Chimie des Materiaux de Strasbourg
Giacomo Ghiringhelli
Politecnico di Milano
Communications Materials
26624443 (eISSN)
Vol. 7 1 250Ämneskategorier (SSIF 2025)
Teoretisk kemi
Den kondenserade materiens fysik
DOI
10.1038/s43246-026-01266-y