Electron-phonon interaction in cuprate-oxide superconductors

TL;DR

This paper introduces a new electron-phonon interaction mechanism in cuprate superconductors, emphasizing its role in phonon softening, quasiparticle kinks, and Cooper pair formation, driven by superexchange modulation and fluctuations.

Contribution

It proposes a novel electron-phonon interaction based on superexchange modulation, highlighting its significance in phonon behavior and superconductivity in cuprates.

Findings

Electron-phonon interaction modulated by superexchange explains phonon softening.

Superexchange fluctuations contribute to quasiparticle dispersion kinks.

Superexchange interaction is key to Cooper pair formation.

Abstract

We propose a novel electron-phonon interaction arising from the modulation of the superexchange interaction by phonons. It is enhanced by spin and superconducting fluctuations, which are developed mainly because of the superexchange interaction. It must be responsible for the softening of phonons and kinks in the dispersion relation of quasi-particles. However, the superexchange interaction must be mainly responsible for the formation of Cooper pairs.