Phonon and Magnetic Pairing Mechanisms in High-Temperature Superconductors in the Strong Correlation Mode

TL;DR

This paper investigates how specific phonon modes influence electron pairing in high-temperature superconductors, revealing that certain phonons can both enhance and suppress pairing, thereby affecting the critical temperature.

Contribution

It introduces a model combining electron interactions with multiple phonon modes, showing their opposite effects on d-symmetry pairing in high-Tc superconductors.

Findings

Buckling phonon mode promotes electron pairing.

Breathing phonon mode suppresses pairing.

Inclusion of phonons lowers the critical temperature.

Abstract

The t-t'-t''-J model of electrons interacting with three phonon modes (breathing, apical breathing, and buckling) is considered. The wave-vector dependence of the matrix elements of the electron-phonon interaction leads to opposite contributions to the pairing potential with the d-symmetry: the buckling mode facilitates electron pairing, while the breathing mode suppresses it. As a result, the critical temperature of La{2 - x}Sr{x}CuO{4} that is associated with the magnetic mechanism is lowered when phonons are taken into account.