TY  - JOUR
AU  - Sonntag, Jens
AU  - Reichardt, S.
AU  - Wirtz, L.
AU  - Beschoten, Bernd
AU  - Katsnelson, M. I.
AU  - Libisch, F.
AU  - Stampfer, Christoph
TI  - Impact of Many-Body Effects on Landau Levels in Graphene
JO  - Physical review letters
VL  - 120
IS  - 18
SN  - 1079-7114
CY  - College Park, Md.
PB  - APS
M1  - FZJ-2020-02430
SP  - 187701
PY  - 2018
AB  - 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.
LB  - PUB:(DE-HGF)16
C6  - pmid:29775369
UR  - <Go to ISI:>//WOS:000432979900036
DO  - DOI:10.1103/PhysRevLett.120.187701
UR  - https://juser.fz-juelich.de/record/877732
ER  -