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arXiv · 1003.1936

Phonon switching and combined Fano-Rice effect in optical spectra of bilayer graphene

E. Cappelluti·L. Benfatto·A. B. Kuzmenko
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Abstract

Recent infrared measurements of phonon peaks in gated bilayer graphene reveal two striking signatures of electron-phonon interaction: an asymmetric Fano lineshape and a giant variation of the peak intensity as a function of the applied gate voltage. In this Letter we provide a unified theoretical framework which accounts for both these effects and unveils the occurrence of a switching mechanism between the symmetric ($E_g$) and anti-symmetric ($E_u$) phonon mode as dominant channel in the optical response. A complete phase diagram of the optical phonon response is also presented, as a function of both the charge density and the bandgap.

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E. Cappelluti, L. Benfatto, A. B. Kuzmenko. 2010-03-09. Phonon switching and combined Fano-Rice effect in optical spectra of bilayer graphene. https://doi.org/10.1103/physrevb.82.041402

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