What did the electron 'say' to the phonon in the graphene sandwich?

Electrons carry electrical energy, while vibrational energy is carried by phonons. Understanding how they interact with each other in certain materials, like in a sandwich of two graphene layers, will have implications for future optoelectronic devices. Recent work has revealed that graphene layers twisted relative to each other by a small 'magic angle' can act as perfect insulator or superconductor, but the physics of the electron-phonon interactions behind this are a mystery. As part of a worldwide international collaboration led by TU/e researcher Klaas-Jan Tielrooij, with theoretical contributions by Tokyo Tech's Hiroaki Ishizuka, the team has conducted an in-depth study on electron-phonon interactions in graphene layers, and they have made a startling discovery.

• What did the electron 'say' to the phonon in the graphene sandwich?