On the local approximation of the electron-photon interaction self-energy
Résumé
We investigate the impact of the so-called local, i.e., diagonal, approximation for the electron-photon scattering self-energy, within the nonequilibrium Green's function formalism. We report on three different systems to show that the local approximation may dramatically degrade expected selection rules, but that this degradation has minor impacts on the physical properties of realistic systems in which other scattering processes are assumed.