Correlated electronic structure, orbital-selective behavior, and magnetic correlations in double-layer La3Ni2 O7 under pressure

Abstract

Using ab initio band structure and DFT+dynamical mean-field theory methods we examine the effects of electron-electron interactions on the normal state electronic structure, Fermi surface, and magnetic correlations of the recently discovered double-layer perovskite superconductor La3Ni2O7 under pressure. Our results suggest the formation of a negative charge transfer mixed-valence state with the Ni valence close to 1.75+. We find a remarkable orbital-selective renormalization of the Ni 3d bands, with m∗/m∼3 and 2.3 for the Ni 3z2-r2 and x2-y2 orbitals, respectively, in agreement with experimental estimates. Our results for the k-dependent spectral functions and Fermi surfaces show significant incoherence of the Ni 3z2-r2 states, implying the proximity of the Ni 3d states to orbital-dependent localization. Based on our analysis of the static magnetic susceptibility, we propose the possible formation of the spin and charge (or bond) density wave stripe states in high-pressure La3Ni2O7. © 2023 American Physical Society.