Doping evolution of lanthanide-derived electronic bands

Determine how the hybridized lanthanide 5d/4f bands in infinite-layer nickelates evolve with hole doping, including whether their occupation is depleted in La-based and Nd-based compounds and how this evolution affects the proposed RKKY-mediated coupling between local moments.

Background

The paper interprets the persistence of local moments and glassy freezing across the (La,Sr)NiO₂ phase diagram within a multiorbital framework. In this interpretation, itinerant electron pockets formed from hybridized lanthanide 5d/4f and Ni orbitals may mediate RKKY interactions between localized Ni moments.

The authors note conflicting experimental indications: optical conductivity on Nd-based nickelates suggests that hole doping depletes, but does not eliminate, the electron pocket, whereas x-ray absorption measurements on La-based compounds indicate that doping primarily transfers spectral weight from Ni 3d to O 2p orbitals without substantially changing the La 5d/4f occupation. Resolving the doping evolution of these bands is therefore necessary for explaining the observed weakening of magnetic interactions with increased hole concentration.