Angle-resolved photoemission spectra of graphene from first-principles calculations

TL;DR

This paper presents first-principles simulations of ARPES spectra for graphene, capturing many-body interactions such as electron-electron and electron-phonon effects, and reproduces key experimental features like Dirac cone asymmetry.

Contribution

It introduces a comprehensive ab initio approach to simulate ARPES spectra of graphene including both electron-electron and electron-phonon interactions.

Findings

Reproduces experimental ARPES features of graphene

Identifies mismatch between Dirac cone halves

Highlights importance of many-body effects in spectra

Abstract

Angle-resolved photoemission spectroscopy (ARPES) is a powerful experimental technique for directly probing electron dynamics in solids. The energy vs. momentum dispersion relations and the associated spectral broadenings measured by ARPES provide a wealth of information on quantum many-body interaction effects. In particular, ARPES allows studies of the Coulomb interaction among electrons (electron-electron interactions) and the interaction between electrons and lattice vibrations (electron-phonon interactions). Here, we report ab initio simulations of the ARPES spectra of graphene including both electron-electron and electron-phonon interactions on the same footing. Our calculations reproduce some of the key experimental observations related to many-body effects, including the indication of a mismatch between the upper and lower halves of the Dirac cone.