Article

Double Resonant Raman Scattering in Graphite

Institut fur Festkorperphysik, Technische Universitat Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
Physical Review Letters (Impact Factor: 7.51). 01/2001; 85(24):5214-7. DOI: 10.1103/PhysRevLett.85.5214
Source: PubMed

ABSTRACT We find that the electronic dispersion in graphite gives rise to double resonant Raman scattering for excitation energies up to 5 eV. As we show, the curious excitation-energy dependence of the graphite $D$ mode is due to this double resonant process resolving a long-standing problem in the literature and invalidating recent attempts to explain this phenomenon. Our calculation for the $D$-mode frequency shift ( $60{\mathrm{cm}}^{\ensuremath{-}1}/\mathrm{eV}$) agrees well with the experimental value.

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