  Twisted 2D layered materials have garnered a lot of attention recently as a
class of 2D materials whose interlayer interactions and electronic properties
are dictated by the relative rotation / twist angle between the adjacent
layers. In this work, we explore a prototype of such a twisted 2D system,
artificially stacked twisted bilayer graphene (TBLG), where we probe the
changes in the interlayer interactions and electron-phonon scattering pathways
as the twist angle is varied from 0{\deg} to 30{\deg}, using Raman
spectroscopy. The long range Moir\'e potential of the superlattice gives rise
to additional intravalley and intervalley scattering of the electrons in TBLG
which have been investigated through their Raman signatures. The density
functional theory (DFT) calculations of the electronic band structure of the
TBLG superlattices was found to be in agreement with the resonant Raman
excitations across the van Hove singularities in the valence and conduction
bands predicted for TBLG due to hybridization of bands from the two layers. We
also observe that the relative rotation between the graphene layers has a
marked influence on the second order overtone and combination Raman modes
signalling a commensurate-incommensurate transition in TBLG as the twist angle
increases. This serves as a convenient and rapid characterization tool to
determine the degree of commensurability in TBLG systems.
