Fermi surfaces, electron-hole asymmetry and correlation kink in a three-dimensional Fermi liquid LaNiO$_3$

TL;DR

This study uses 3D soft x-ray photoemission to investigate LaNiO$_3$, revealing momentum-dependent electron-hole asymmetry, correlation kinks at 0.25 eV, and differences in self-energy behavior between electron and hole Fermi surfaces.

Contribution

It provides the first detailed 3D momentum-resolved analysis of LaNiO$_3$'s Fermi surfaces, highlighting electron-hole asymmetry and correlation effects not captured by standard calculations.

Findings

Observation of 3D electron and hole Fermi surfaces.

Identification of a correlation kink at 0.25 eV.

Momentum-dependent mass renormalization leading to electron-hole asymmetry.

Abstract

We report the three-dimensional (3-D) momentum-resolved soft x-ray photoemission spectroscopy of the Fermi liquid LaNiO$_3$. The out-of-plane and in-plane cuts of the 3-D electron- and hole-Fermi surfaces (FSs) are observed by energy- and angle- dependent photoemission measurements. The energy bands forming the electron FS suggest an $\omega^2$ dependence of the imaginary part of the self-energy and a `correlation kink' at an energy scale of 0.25 eV. In contrast, the bands which form nesting character hole FSs do not show kinks and match local density approximation calculations. The results indicate a momentum-dependent mass renormalization, leading to electron-hole asymmetry in strongly correlated LaNiO$_3$.