▎ 摘　　要

The present work deals with the analysis of the single particle spectral function of monolayer and bilayer (AB- and AA-stacked) graphene. The tight binding Hamiltonian containing nearest-neighbor and next-nearest neighbor hopping with in two triangular sub-lattice approach for monolayer graphene, and along-with the interlayer coupling parameter for bilayer graphene has been employed. The expressions of single particle spectral functions A(kw) is obtained within Green's function equations of motion approach exactly. The spectral function at F, M and K points of the Brillouin zone is numerically calculated. It is found that the electronic states close to Dirac (K) points are more important to pin point the nature of the electronic properties of graphene. The next-nearest-neighbor hopping shifts the quasi particle peak close to Fermi level and introduce a particle-hole asymmetry in the electronic spectrum while the onsite Coulomb interaction suppress the quasi particle peak (close to Fermi level) and shift the spectral weight away from Fermi level. On the other hand interlayer coupling is found to be responsible for the splitting of quasi particle spectral peak at each point of Brillouin zone and prominently influence the electronic spectrum in AA-stacked as compared to AB-stacked bilayer graphene.