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Updated: Dec 27, 2025

Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
Published on: April 28, 2016
Non-linear Raman scattering intensities in graphene
Veit Giegold1, Lucas Lange1, Richard Ciesielski1
1Department of Chemistry and Center for NanoScience (CeNS), LMU Munich, Butenandtstr. 5-13, 81377 Munich, Germany. veit.giegold@cup.lmu.de achim.hartschuh@lmu.de.
Abstract:
We show that the Raman scattering signals of the two dominant Raman bands G and 2D of graphene sensitively depend on the laser intensity in opposite ways. High electronic temperatures reached for pulsed laser excitation lead to an asymmetric Fermi-Dirac distribution at the different optically resonant states contributing to Raman scattering. This results in a partial Pauli blocking of destructively interfering quantum pathways for G band scattering, which is observed as a super-linear increase of the G band intensity with laser power. The 2D band, on the other hand, exhibits sub-linear intensity scaling due to the blocking of constructively interfering contributions. The opposite intensity dependencies of the two bands are found to reduce the observed 2D/G ratio, a key quantity used for characterizing graphene samples, by more than factor two for electronic temperatures around 3000 K.
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