Electronic properties of AA-stacked nanographite ribbons

The interlayer interactions in the AA-stacked nanographite ribbons significantly affect density of states, energy gap, band structure, and free carriers. Density of states exhibits many special structures, including plateau, discontinuities, and divergent peaks. Energy gaps of the semiconducting armchair ribbons decline rapidly as the number of ribbons increases. Most of them could exhibit the semiconductor–semimetal transition. Zigzag ribbons are metallic for any ribbon number, while the low energy density of states is drastically changed by the interlayer interactions. Carrier density also depends on the ribbon width and the edge structure. The AA-stacked nanographite ribbons quite differ from the graphite layers or the AB-stacked nanographite ribbons.