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arXiv · 1406.4226

Breit-Wigner-Fano lineshapes in Raman spectra of graphene

Eddwi H. Hasdeo·Ahmad R. T. Nugraha·Mildred S. Dresselhaus·Riichiro Saito
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Abstract

Excitation of electron-hole pairs in the vicinity of the Dirac cone by the Coulomb interaction gives rise to an asymmetric Breit-Wigner-Fano lineshape in the phonon Raman spectra in graphene. This asymmetric lineshape appears due to the interference effect between the phonon spectra and the electron-hole pair excitation spectra. The calculated Breit-Wigner-Fano asymmetric factor 1/qBWF as a function of the Fermi energy shows a V-shaped curve with a minimum value at the charge neutrality point and gives good agreement with the experimental result.

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Eddwi H. Hasdeo, Ahmad R. T. Nugraha, Mildred S. Dresselhaus, Riichiro Saito. 2014-06-17. Breit-Wigner-Fano lineshapes in Raman spectra of graphene. https://doi.org/10.1103/physrevb.90.245140

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