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arXiv · 0704.0027

Filling-Factor-Dependent Magnetophonon Resonance in Graphene

M. O. Goerbig·J. -N. Fuchs·K. Kechedzhi·Vladimir I. Fal'ko
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Abstract

We describe a peculiar fine structure acquired by the in-plane optical phonon at the Gamma-point in graphene when it is brought into resonance with one of the inter-Landau-level transitions in this material. The effect is most pronounced when this lattice mode (associated with the G-band in graphene Raman spectrum) is in resonance with inter-Landau-level transitions 0 -> (+,1) and (-,1) -> 0, at a magnetic field B_0 ~ 30 T. It can be used to measure the strength of the electron-phonon coupling directly, and its filling-factor dependence can be used experimentally to detect circularly polarized lattice modes.

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M. O. Goerbig, J. -N. Fuchs, K. Kechedzhi, Vladimir I. Fal'ko. 2009-09-24. Filling-Factor-Dependent Magnetophonon Resonance in Graphene. https://doi.org/10.1103/physrevlett.99.087402

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