Energy bands of multilayer graphenes

The energy bands of L-layer graphenes have been obtained using first-principles calculations. We found that after the introduction of interlay coupling the linear valence and conduction bands of isolated layers can either remain or develop into parabolic bands or bands with a very flat top(bottom), depending on the stacking geometry. A theoretical explanation and some general rules have been developed based upon the tight-binding model with only the nearest-neighbor interactions.