Abstract

Electron-phonon interactions play a central role in determining the spectral and transport properties of electrons at room temperature. In this talk, I will present an ab initio Green’s function-based framework for studying these effects. I will begin with a self-consistent approach to spectral functions, which can capture satellite features more accurately than the widely used Dyson-Migdal and cumulant approximations. Building on this result, I will then discuss electronic transport. By solving the ladder equations for the linear response of Green’s functions, one can account for both beyond-quasiparticle effects and vertex corrections at the same time. This approach unifies and improves upon two state-of-the-art approaches for ab initio phonon-limited transport: the Boltzmann transport equation and the bubble approximation. Finally, I will demonstrate applications of these methods to real semiconductors and metals, highlighting results for spectral functions, DC conductivity, and THz optical properties.

Jae-Mo Lihm and Samuel Ponce, Phys. Rev. Lett. 134, 186401 (2025); arXiv: 2506.18139 (2025)