  The magneto-phonon resonance or MPR occurs in semiconductor materials when
the energy spacing between Landau levels is continuously tuned to cross the
energy of an optical phonon mode. MPRs have been largely explored in bulk
semiconductors, in two-dimensional systems and in quantum dots. Recently there
has been significant interest in the MPR interactions of the Dirac fermion
magnetoexcitons in graphene, and a rich splitting and anti-crossing phenomena
of the even parity E2g long wavelength optical phonon mode have been
theoretically proposed and experimentally observed. The MPR has been found to
crucially depend on disorder in the graphene layer. This is a feature that
creates new venues for the study of interplays between disorder and
interactions in the atomic layers. We review here the fundamentals of MRP in
graphene and the experimental Raman scattering works that have led to the
observation of these phenomena in graphene and graphite.
