Oxide Fermi liquid universality revealed by electron spectroscopy

TL;DR

This study uses advanced electron spectroscopy to reveal that electron-overdoped cuprates exhibit a universal Fermi liquid behavior characterized by a logarithmic relation between quasiparticle scattering rate and mass, despite differences in electron correlations.

Contribution

It demonstrates a universal Fermi liquid relation in oxide systems through spectroscopic analysis, highlighting a single energy scale governing quasiparticle properties.

Findings

Logarithmic divergence between scattering rate and mass observed

Momentum isotropic and weak electron correlations in PLCCO

Fermi liquid quasiparticle lifetime and mass linked by a single energy scale

Abstract

We present a combined soft x-ray and high-resolution vacuum-ultraviolet angle-resolved photoemission spectroscopy study of the electron-overdoped cuprate Pr$_{1.3-x}$La$_{0.7}$Ce$_{x}$CuO$_4$ (PLCCO). Demonstration of its highly two-dimensional band structure enabled precise determination of the in-plane self-energy dominated by electron-electron scattering. Through analysis of this self-energy and the Fermi-liquid cut-off energy scale, we find -- in contrast to hole-doped cuprates -- a momentum isotropic and comparatively weak electron correlation in PLCCO. Yet, the self-energies extracted from multiple oxide systems combine to demonstrate a logarithmic divergent relation between the quasiparticle scattering rate and mass. This constitutes a spectroscopic version of the Kadowaki-Woods relation with an important merit -- the demonstration of Fermi liquid quasiparticle lifetime and mass being set by a single energy scale.