Speaker
Description
We investigate magnetism in the electron-doped infinite-layer nickelate NdNiO$_2$ within a multi-orbital tight-binding framework including both Ni and Nd states. The model captures the self-doping effect arising from charge transfer into Nd bands. For realistic parameters, we find that undoped NdNiO$_2$ lies just outside the antiferromagnetic (AFM) region of the phase diagram, consistent with the absence of long-range order and the presence of short-range AFM correlations and broad magnetic excitations observed experimentally.
Electron doping markedly enhances the stability of AFM order via the self-doping mechanism, in clear contrast to the behavior of cuprates. For reduced charge-transfer energies, self-doping becomes stronger and stabilizes stripe-like configurations already at the mean-field level [1]. These results highlight the central role of Nd-derived states and suggest that incorporating correlation effects beyond conventional mean-field theory, for instance using so-called ghost-Gutzwiller approach [2], may provide a more complete quantitative description.
We acknowledge support from the National Science Centre (NCN, Poland) under Projects No. 2021/43/B/ST3/02166 and No. 2024/55/B/ST3/03144.
[1] Adam Kłosiński, Roman Drachynskyi, Krzysztof Wohlfeld, and Wojciech Brzezicki, Phys. Rev. B 113, 085148 (2026).
[2] Carlos Mejuto-Zaera and Michele Fabrizio, Phys. Rev. B 107, 235150 (2023).