Many-body effects resulting from strong electron-electron and electron-phonon interactions play a significant role in graphene physics. We report on their manifestation in low B field magneto-phonon resonances in high quality exfoliated single-layer and bilayer graphene encapsulated in hexagonal boron nitride. These resonances allow us to extract characteristic effective Fermi velocities, as high as 1.20×106 m/s, for the observed "dressed" Landau level transitions, as well as the broadening of the resonances, which increases with Landau level index.
@article{arxiv.1504.03555,
title = {Low B Field Magneto-Phonon Resonances in Single-Layer and Bilayer Graphene},
author = {Christoph Neumann and Sven Reichardt and Marc Drögeler and Bernat Terrés and Kenji Watanabe and Takashi Taniguchi and Bernd Beschoten and Slava V. Rotkin and Christoph Stampfer},
journal= {arXiv preprint arXiv:1504.03555},
year = {2021}
}