  Femtosecond time-resolved spectroscopy using 400 nm-pump and 800 nm-probe in
CVD-grown multilayer graphene provides strong evidence for isotropic
distribution of photoexcited carrier after initial relaxation. Indicative of
such isotropic distribution is a pump polarization independence of differential
reflectivity (\DeltaR/R) and transmittance (\DeltaT/T) from pump-probe
measurements. Combined with results using 800 nm-pump in [arXiv. 1301.1743v3
(2013)], these pump polarization dependences of time-resolved spectroscopy
corroborates the evolution of photo-excited carrier distribution from
anisotropic to isotropic with carrier relaxation. And, the absorbance of
graphene is identical for in-plane and out-of-plane optical fields. No matter
the carrier distribution in momentum space, the influence of carrier on
in-plane and out-of-plane optical fields from state filling effect is
identical. The sign reversing of ps dynamics signal in graphene/graphite should
not directly relate to carrier.
