Chemistry Reference
In-Depth Information
Fig. 3.20
FWHM of the
plasmon peak as a function of
a
the parallel momentum
transfer
q
||
and of
b
the
plasmon energy. The inset in
the top panel shows the origin
of interband SPEs from
π
to
π
∗
bands. The Fermi wave
vector represents the onset
where plasmon enters the
damping region
3.4.3
Dispersion and Damping Processes of
π
Plasmon
The electronic response of graphene systems is related to the collective excitations
of the electrons which combine in-plane and inter-plane interactions. Herein we
want to investigate the nature and the dispersion of
π
plasmon in MLG grown on a
metal substrate. The
plasmon is a sensitive probe of the graphene band structure
near the Fermi level (Sun et al.
2010
). Its physical origin is the electric dipole
transition between the
π
π
energy bands (
π → π
*) mainly in the region of the M
