Unconventional pressure-dependent interorbital and interlayer doping in superconducting nickelates

Abstract

The discovery of nickelate superconductivity provided the first example of a non-copper-based material with superconductivity strongly analogous to the cuprates. However, recent findings raise questions and inconsistencies around the electron counts and doping phase diagrams. We show using superconducting La4⁢Ni3⁢O10 that there are unconventional interlayer and interorbital intrinsic doping effects that render the 𝑑𝑥2−𝑦2 occupation similar to the cuprates. The results enable a consistent framework for nickelate superconductivity, while maintaining the connection between cuprate and nickelate superconductors.