Authors: S Kumar Ajay
Publish Date: 2014/05/07
Volume: 88, Issue: 8, Pages: 813-829
Abstract
Present work deals with the analysis of the single particle electronic spectral function in trilayer ABC ABA and AAAstacked graphene Tight binding Hamiltonian containing intralayer nearestneighbor and nextnearest neighbor hopping alongwith the interlayer coupling parameter within two triangular sublattice approach for trilayer graphene has been employed The expression of single particle spectral functions Akw is obtained within meanfield Green’s function equations of motion approach Spectral function at Γ M and K points of the Brillouin zone has been numerically computed It is pointed out that the nature of electronic states at different points of Brillouin zone is found to be influenced by stacking order and Coulomb interactions At Γ and M points a trilayer splitting is predicted while at K point a bilayer splitting effect is observed due to crossing of two bands at K point Interlayer coupling t bot is found to be responsible for the splitting of quasiparticle peaks at each point of Brillouin zone The influence of t bot in trilayer graphene is prominent for AAAstacking compared to ABC and ABAstacking On the other hand onsite Coulomb interaction reduces the trilayer splitting effect into bilayer splitting at Γ and M points of Brillouin zone and bilayer splitting into single peak spectral function at K point with a shifting of the peak away from Fermi level
Keywords: