Dichotomy in Low- and High-Energy Band Renormalizations in Trilayer Nickelate : A Comparison with Cuprates
Phys. Rev. Lett. 135, 146506 – Published 1 October, 2025
DOI: https://doi.org/10.1103/smkf-k7wq
Abstract
Band renormalizations comprise crucial insights for understanding the intricate roles of electron-boson coupling and electron correlation in emergent phenomena such as superconductivity. In this Letter, by combining high-resolution angle-resolved photoemission spectroscopy and theoretical calculations, we systematically investigate the electronic structure of the trilayer nickelate superconductor at ambient pressure. We reveal a dichotomy in the electronic band renormalizations of in comparison to cuprate superconductors. At a high energy scale of hundreds of meV, its band structure is strongly renormalized by an electron correlation effect enhanced by Hund’s coupling. The resultant waterfall-like dispersions resemble the high-energy kinks in cuprate superconductors. However, at low-energy scales of tens of meV, the dispersive bands are nearly featureless and devoid of any resolvable electron-boson interactions, in drastic contrast to the low-energy kinks observed in cuprates and other correlated transition-metal compounds. The dichotomic band renormalizations highlight the disparity between nickelate and cuprate superconductors and emphasize the importance of strong electron correlation in the superconductivity of Ruddlesden-Popper phase nickelates.