[en] We present magneto-Raman spectroscopy measurements on suspended graphene to investigate the charge carrier density-dependent electron-electron interaction in the presence of Landau levels. Utilizing gate-tunable magnetophonon resonances, we extract the charge carrier density dependence of the Landau level transition energies and the associated effective Fermi velocity vF. In contrast to the logarithmic divergence of vF at zero magnetic field, we find a piecewise linear scaling of vF as a function of the charge carrier density, due to a magnetic-field-induced suppression of the long-range Coulomb interaction. We quantitatively confirm our experimental findings by performing tight-binding calculations on the level of the Hartree-Fock approximation, which also allow us to estimate an excitonic binding energy of ≈6 meV contained in the experimentally extracted Landau level transitions energies.
FnR ; FNR10196198 > Sven Reichardt > RAMGRASEA > Calculation of Raman Spectra of Graphene in Various Conditions with a Semi-Empirical Approach > 15/02/2015 > 31/03/2018 > 2015;FNR7490149 > Ludger Wirtz > NANOTMD > 20 Electric transport and superconductivity in TransitionMetal Dichalcogenides nanolayers > 01/02/2014 > 31/01/2019 > 2013
[University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Physics and Materials Science Research Unit >]
