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arXiv · 1008.1206

Observation of magneto-phonon resonance of Dirac fermions in graphite

J. Yan·S. Goler·T. D. Rhone·M. Han·R. He·P. Kim·V. Pellegrini·A. Pinczuk
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Abstract

Coherent coupling of Dirac fermion magneto-excitons with an optical phonon is observed in graphite as marked magnetic-field dependent splittings and anti-crossing behavior of the two coupled modes. The sharp magneto-phonon resonance occurs in regions of the graphite sample with properties of superior single-layer graphene having enhanced lifetimes of Dirac fermions. The greatly reduced carrier broadening to values below the graphene electron-phonon coupling constant explains the appearance of sharp resonances that reveal a fundamental interaction of Dirac fermions.

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J. Yan, S. Goler, T. D. Rhone, M. Han, R. He, P. Kim, V. Pellegrini, A. Pinczuk. 2010-08-06. Observation of magneto-phonon resonance of Dirac fermions in graphite. https://doi.org/10.1103/physrevlett.105.227401

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