# Many-body effects in doped graphene on a piezoelectric substrate

## TL;DR

This paper studies how piezoelectric substrate phonons affect the electronic properties of doped graphene, highlighting the importance of screening effects and comparing substrate and intrinsic phonon interactions.

## Contribution

It provides a detailed analysis of electron-phonon interactions in graphene on piezoelectric substrates, including self-energy calculations and mobility limitations, with emphasis on screening effects.

## Key findings

- Substrate phonons dominate over intrinsic phonons at low doping levels.
- Proper screening of electron-phonon vertex is crucial for accurate modeling.
- Substrate phonons significantly influence electron mobility at various temperatures.

## Abstract

We investigate the many-body properties of graphene on top of a piezoelectric substrate, focusing on the interaction between the graphene electrons and the piezoelectric acoustic phonons. We calculate the electron and phonon self-energies as well as the electron mobility limited by the substrate phonons. We emphasize the importance of the proper screening of the electron-phonon vertex and discuss the various limiting behaviors as a function of electron energy, temperature, and doping level. The effect on the graphene electrons of the piezoelectric acoustic phonons is compared with that of the intrinsic deformation acoustic phonons of graphene. Substrate phonons tend to dominate over intrinsic ones for low doping levels at high and low temperatures.