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arXiv · 1204.6356

Direct Observation of Inner and Outer G' Band Double-resonance Raman Scattering in Free Standing Graphene

Zhiqiang Luo·Chunxiao Cong·Jun Zhang·Qihua Xiong·Ting Yu
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Abstract

In contrary to the widely reported single and symmetric peak feature of G' (or 2D) band in Raman spectrum of graphene, we herein report the observation of splitting in G' band in free standing graphene. Our experimental findings provide a direct and strong support for the previous theoretical prediction that the coexistence of the outer and inner processes in the doubleresonance Raman scattering would cause the splitting of G' mode. Our investigation of the influence of trigonal warping effect on the spectral features of G' subbands further verified the theoretical interpretation established on the anisotropic electronic structure of graphene.

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Zhiqiang Luo, Chunxiao Cong, Jun Zhang, Qihua Xiong, Ting Yu. 2012-04-28. Direct Observation of Inner and Outer G' Band Double-resonance Raman Scattering in Free Standing Graphene. https://doi.org/10.1063/1.4729407

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