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arXiv · 0803.4031

Van Hove Singularity and Apparent Anisotropy in the Electron-Phonon Interaction in Graphene

Cheol-Hwan Park·Feliciano Giustino·Jessica L. McChesney·Aaron Bostwick·Taisuke Ohta·Eli Rotenberg·Marvin L. Cohen·Steven G. Louie
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Abstract

We show that the electron-phonon coupling strength obtained from the slopes of the electronic energy vs. wavevector dispersion relations, as often done in analyzing angle-resolved photoemission data, can differ substantially from the actual electron-phonon coupling strength due to the curvature of the bare electronic bands. This effect becomes particularly important when the Fermi level is close to a van Hove singularity. By performing {\it ab initio} calculations on doped graphene we demonstrate that, while the apparent strength obtained from the slopes of experimental photoemission data is highly anisotropic, the angular dependence of the actual electron-phonon coupling strength in this material is negligible.

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Cheol-Hwan Park, Feliciano Giustino, Jessica L. McChesney, Aaron Bostwick, Taisuke Ohta, Eli Rotenberg, Marvin L. Cohen, Steven G. Louie. 2008-03-28. Van Hove Singularity and Apparent Anisotropy in the Electron-Phonon Interaction in Graphene. https://doi.org/10.1103/physrevb.77.113410

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