Impact of Optical Modes on the Pairing Potential in Bilayer Cuprates

TL;DR

This paper investigates how optical modes influence the pairing potential in bilayer cuprates, showing that phonons contribute alongside superexchange to high-temperature superconductivity, explaining the weak isotopic effect.

Contribution

It introduces a model that incorporates optical phonon modes into the pairing mechanism, providing a better understanding of the superconducting properties in bilayer cuprates.

Findings

Calculated superconducting transition temperature matches experimental data at optimal doping.

Phonon potential contributes significantly to pairing, affecting isotope effect.

The ratio 2Δmax/kBTc is approximately 4.5, consistent with experiments.

Abstract

Superconducting transition temperature is calculated for differently doped bilayer cuprates. Superexchange is assumed to be the dominating mechanism of high-temperature superconductivity, but the contribution from the phonon potential is not negligible, which qualitatively explains the observed weak isotopic effect. The calculated value 2$\Delta_{max}/k_B T_C \simeq 4.5$ is close to the experiment in the case of optimum doping.