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arXiv · 1112.3884

Magnetophonon resonance in graphite: High-field Raman measurements and electron-phonon coupling contributions

Y. Kim·Y. Ma·A. Imambekov·N. G. Kalugin·A. Lombardo·A. C. Ferrari·J. Kono·D. Smirnov
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Abstract

We perform Raman scattering experiments on natural graphite in magnetic fields up to 45 T, observing a series of peaks due to interband electronic excitations over a much broader magnetic field range than previously reported. We also explore electron-phonon coupling in graphite via magnetophonon resonances. The Raman G peak shifts and splits as a function of magnetic field, due to the magnetically tuned coupling of the E2g optical phonons with the K- and H-point inter-Landau-level excitations. The analysis of the observed anticrossing behavior allows us to determine the electron-phonon coupling for both K- and H-point carriers. In the highest field range (>35 T) the G peak narrows due to suppression of electron-phonon interaction.

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Y. Kim, Y. Ma, A. Imambekov, N. G. Kalugin, A. Lombardo, A. C. Ferrari, J. Kono, D. Smirnov. 2012-03-13. Magnetophonon resonance in graphite: High-field Raman measurements and electron-phonon coupling contributions. https://doi.org/10.1103/physrevb.85.121403

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