Theory of infrared double-resonance Raman spectrum in graphene: the role of the zone-boundary electron-phonon enhancement

TL;DR

This paper provides a detailed theoretical analysis of the infrared double-resonance Raman spectrum in monolayer graphene, emphasizing the role of zone-boundary electron-phonon interactions and their impact on material properties.

Contribution

It advances the understanding of electron-phonon enhancement effects in graphene using first-principles calculations, improving upon previous models and connecting to experimental observations.

Findings

Electron-phonon enhancement significantly influences Raman spectra.

Theoretical predictions align better with experimental data.

Resistivity at room temperature is affected by the electron-phonon interactions.

Abstract

We theoretically investigate the double-resonance Raman spectrum of monolayer graphene down to infrared laser excitation energies. By using first-principles density functional theory calculations, we improve upon previous theoretical predictions based on conical models or tight-binding approximations, and rigorously justify the evaluation of the electron-phonon enhancement found in Ref. [Venanzi, T., Graziotto, L. et al., Phys. Rev. Lett. 130, 256901 (2023)]. We proceed to discuss the effects of such enhancement on the room temperature graphene resistivity, hinting towards a possible reconciliation of theoretical and experimental discrepancies.