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arXiv · 0807.1631

Phonon renormalisation in doped bilayer graphene

A. Das·B. Chakraborty·S. Piscanec·S. Pisana·A. K. Sood·A. C. Ferrari
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Abstract

We report phonon renormalisation in bilayer graphene as a function of doping. The Raman G peak stiffens and sharpens for both electron and hole doping, as a result of the non-adiabatic Kohn anomaly at the $Γ$ point. The bilayer has two conduction and valence subbands, with splitting dependent on the interlayer coupling. This results in a change of slope in the variation of G peak position with doping, which allows a direct measurement of the interlayer coupling strength.

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A. Das, B. Chakraborty, S. Piscanec, S. Pisana, A. K. Sood, A. C. Ferrari. 2008-07-10. Phonon renormalisation in doped bilayer graphene. https://doi.org/10.1103/physrevb.79.155417

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