Comparative Many-Body Study of Pr$_4$Ni$_3$O$_8$ and NdNiO$_2$

TL;DR

This study compares the many-body electronic structures of two nickelates, Pr$_4$Ni$_3$O$_8$ and NdNiO$_2$, revealing similarities in their correlated Ni-$3d$ shells and their proximity to the Mott-Hubbard regime, with differences in doping mechanisms.

Contribution

It provides a detailed comparison of the many-body electronic structures of Pr$_4$Ni$_3$O$_8$ and NdNiO$_2$ using density functional plus dynamical mean field theory, highlighting their similarities and differences.

Findings

Similar many-body configurations in Ni-$3d$ shells

Comparable electronic structures at same carrier concentration

Closer to Mott-Hubbard regime than cuprates

Abstract

We study the many-body electronic structure of the stoichiometric and electron-doped trilayer nickelate Pr$_4$Ni$_3$O$_8$ in comparison to that of the stoichiometric and hole-doped infinite layer nickelate NdNiO$_2$ within the framework of density functional plus dynamical mean field theory, noting that Pr$_4$Ni$_3$O$_8$ has the same nominal carrier concentration as NdNiO$_2$ doped to a level of 1/3 holes/Ni. We find that the correlated Ni-$3d$ shells of both of these low valence nickelates have similar many-body configurations with correlations dominated by the $d_{x^2-y^2}$ orbital. Additionally, when compared at the same nominal carrier concentration, the materials exhibit similar many-body electronic structures, self energies, and correlation strengths. Compared to cuprates, these materials are closer to the Mott-Hubbard regime due to their larger charge transfer energies. Moreover, doping involves the charge reservoir provided by the rare earth $5d$ electrons, as opposed to cuprates where it is realized via the oxygen $2p$ electrons.