Hopping-resolved electron-phonon coupling in bilayer graphene

TL;DR

This study quantitatively analyzes electron-phonon coupling in bilayer graphene using DFT, revealing a scaling law between interlayer hopping parameters and coupling strength, advancing understanding of multilayer graphene interactions.

Contribution

It introduces a quantitative evaluation of electron-phonon coupling for each interlayer hopping in bilayer graphene using a frozen-phonon DFT approach, uncovering a universal scaling law.

Findings

Identified a simple scaling law between hopping parameters and electron-phonon coupling.

Quantitatively evaluated coupling constants for different interlayer hoppings.

Demonstrated the applicability of the approach across different DFT methods.

Abstract

In this paper we investigate the electron-phonon coupling in bilayer graphene, as a paradigmatic case for multilayer graphenes where interlayer hoppings are relevant. Using a frozen-phonon approach within the context of Density Functional Theory (DFT) and using different optical phonon displacements we are able to evaluate quantitatively the electron-phonon coupling $\alpha_i$ associated with each hopping term $\gamma_i$. This analysis also reveals a simple scaling law between the hopping terms $\gamma_i$ and the electron-phonon coupling $\alpha_i$ which goes beyond the specific DFT technique employed.