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arXiv · 1211.6094

Measurement of Filling-Factor-Dependent Magnetophonon Resonances in Graphene Using Raman Spectroscopy

Y. Kim·J. M. Poumirol·A. Lombardo·N. G. Kalugin·T. Georgiou·Y. J. Kim·K. S. Novoselov·A. C. Ferrari·J. Kono·O. Kashuba·V. I. Fal'ko·D. Smirnov
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Abstract

We perform polarization-resolved Raman spectroscopy on graphene in magnetic fields up to 45T. This reveals a filling-factor-dependent, multi-component anticrossing structure of the Raman G peak, resulting from magnetophonon resonances between magnetoexcitons and E$_{2g}$ phonons. This is explained with a model of Raman scattering taking into account the effects of spatially inhomogeneous carrier densities and strain. Random fluctuations of strain-induced pseudo-magnetic fields lead to increased scattering intensity inside the anti-crossing gap, consistent with the experiment.

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Y. Kim, J. M. Poumirol, A. Lombardo, N. G. Kalugin, T. Georgiou, Y. J. Kim, K. S. Novoselov, A. C. Ferrari, J. Kono, O. Kashuba, V. I. Fal'ko, D. Smirnov. 2013-06-19. Measurement of Filling-Factor-Dependent Magnetophonon Resonances in Graphene Using Raman Spectroscopy. https://doi.org/10.1103/physrevlett.110.227402

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