Electronic and lattice coupling effects in multilayer nickelates: a comparison with cuprates

We explore electron correlation and electron-phonon coupling in La₄Ni₃O₁₀ using laser- and synchrotron-based ARPES. Similar to high-Tc cuprates, strong spectral renormalization ("high-energy waterfall") appears at hundreds of meV binding energy, far exceeding paramagnon energies. However, low-energy "phonon kinks", typical in cuprates, are absent here. The high-energy waterfall can be captured with orbital-dependent electron correlation effects enhanced by Hund's coupling, while the vanishing electron-phonon coupling highlights the effect of large charge transfer energy of Ni-O. This dichotomy, expected to remain robust under pressure, sheds light on the energy hierarchy of relevant interactions underlying nickelate superconductivity, which is potentially tunable by controling oxygen content and disorder by further sample treatment.