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arXiv · 2406.09271

Spin excitations in Nd1-xSrxNiO2 and YBa2Cu3O7-delta: the influence of Hubbard U

Francesco Rosa·Leonardo Martinelli·Guillaume Krieger·Lucio Braicovich·Nicholas B. Brookes·Giacomo Merzoni·Marco Moretti Sala·Flora Yakhou-Harris·Riccardo Arpaia·Daniele Preziosi·Marco Salluzzo·Maciej Fidrysiak·Giacomo Ghiringhelli
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Abstract

We use Resonant Inelastic X-ray Scattering (RIXS) to compare the doping dependence of magnetic excitations of an Infinite-Layer nickelate to those of a prototypical superconducting cuprate. The polarization analysis of RIXS spectra establishes the dominant spin-flip nature of the mid-infrared peak in both cases. Hole doping leads to opposite behavior of the magnetic energy in the two materials. By fitting the data with an original Hubbard-based model for dynamic susceptibility, we find that t is comparable in the two materials while U is about twice larger in the nickelate. This finding accounts for the smaller magnetic bandwidth of nickelates and for its decrease upon doping.

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Francesco Rosa, Leonardo Martinelli, Guillaume Krieger, Lucio Braicovich, Nicholas B. Brookes, Giacomo Merzoni, Marco Moretti Sala, Flora Yakhou-Harris, Riccardo Arpaia, Daniele Preziosi, Marco Salluzzo, Maciej Fidrysiak, Giacomo Ghiringhelli. 2024-06-13. Spin excitations in Nd1-xSrxNiO2 and YBa2Cu3O7-delta: the influence of Hubbard U. https://arxiv.org/abs/2406.09271

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