Electronic structure and magnetic correlations in trilayer nickelate superconductor La$_4$Ni$_3$O$_{10}$ under pressure

TL;DR

This study investigates the electronic and magnetic properties of trilayer nickelate La$_4$Ni$_3$O$_{10}$ under pressure, revealing correlation effects and magnetic fluctuations that may be key to its superconductivity.

Contribution

It provides a detailed theoretical analysis of the correlation effects and magnetic properties in trilayer nickelates, highlighting their similarities with other nickelate systems and their potential role in superconductivity.

Findings

Site- and orbital-dependent renormalization of Ni 3d bands

Incoherence of Ni d_{3z^2-r^2} states due to correlations

Emergence of competing spin and charge stripe states

Abstract

It has been recently shown that under pressure trilayer Ruddlesden-Popper nickelate La$_4$Ni$_3$O$_{10}$ (LNO) becomes superconducting below a critical temperature $\sim$20 K, in addition to the infinite-layer and bilayer systems. Motivated by this observation, we explore the effects of electron correlations on its electronic structure and magnetic properties using the advanced DFT+dynamical mean-field theory approach. Our results for the normal-state electronic structure and correlation effects in LNO have much in common with the infinite-layer and bilayer nickelates, with a remarkable site- and orbital-dependent renormalizations of the Ni $3d$ bands and notable incoherence of the Ni $d_{3z^2-r^2}$ states, caused by correlation effects. Our analysis of the Fermi surface and magnetic correlations suggests the emergence of competing spin and charge stripe states, implying the importance of in-plane spin fluctuations to explain superconductivity in this material.