Phonons and electron-phonon coupling in graphene-h-BN heterostructures

TL;DR

This study uses first-principles calculations to analyze phonons and electron-phonon interactions in graphene-h-BN heterostructures, revealing stability issues and specific phonon modes influencing electronic properties.

Contribution

It provides the first detailed phonon analysis of graphene-h-BN heterostructures, highlighting stacking stability and electron-phonon coupling characteristics.

Findings

AA and AB' stacking are energetically less stable and dynamically unstable.

Identified low-energy flat phonon branches with BN character.

Evaluated electron-phonon coupling in these phonon modes.

Abstract

First principle calculations of the phonons of graphene-BN heterostructures are presented and compared to those of the constituents. We show that AA and AB' stacking are not only energetically less favoured than AB but also dynamically unstable. We have identified low energy flat phonon branches of BN character with out of plane displacement and evaluated their coupling to electrons in graphene.