Properties of high-T$_C$ copper oxides from the nearly-free electron model

TL;DR

This paper models high-Tc copper oxides using a nearly free-electron approach, revealing how phonon and spin interactions influence pseudogaps, Fermi surface features, and the doping-dependent superconductivity window.

Contribution

It applies the nearly free-electron model to high-Tc cuprates, linking phonon and spin interactions to pseudogap formation and superconductivity confinement.

Findings

Identification of Fermi-surface arcs due to dynamic spin/phonon waves

Correlation between potential modulations and doping levels

Superconductivity confined between two doping limits

Abstract

The generic band structure of high-T$_C$ copper oxides is simulated by the nearly free-electron model (NFE) in two dimensions (2-D) with parameters from band calculations. Interaction between phonons and spin waves will cause potential modulations and pseudogaps, and the strength of the modulations, the wave lengths and the doping, are all related. A Fermi-surface "arc" is found for dynamic spin/phonon waves. The confinement of superconductivity between two limiting dopings can be a result of competition with the pseudogap at low doping and weak coupling at high doping.