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arXiv · 1405.4264

Doping dependence of the Raman spectrum of defected graphene

M. Bruna·A. K. Ott·M. Ijas·D. Yoon·U. Sassi·A. C. Ferrari
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Abstract

We investigate the evolution of the Raman spectrum of defected graphene as a function of doping. Polymer electrolyte gating allows us to move the Fermi level up to 0.7eV, as monitored by \textit{in-situ} Hall-effect measurements. For a given number of defects, we find that the intensities of the D and D' peaks decrease with increasing doping. We assign this to an increased total scattering rate of the photoexcited electrons and holes, due to the doping-dependent strength of electron-electron scattering. We present a general relation between D peak intensity and defects valid for any doping level

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M. Bruna, A. K. Ott, M. Ijas, D. Yoon, U. Sassi, A. C. Ferrari. 2014-05-16. Doping dependence of the Raman spectrum of defected graphene. https://arxiv.org/abs/1405.4264

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