Electronic Conduction through Monolayer Amorphous Carbon Nanojunctions

In molecular electronic conduction, exotic lattice morphologies often give rise to exotic behaviors. Among 2D systems, graphene is a notable example. Recently, a stable amorphous version of graphene called monolayer amorphous carbon (MAC) was synthesized. MAC poses a new set of questions regarding the effects of disorder on conduction. In this Letter, we perform an ensemble-level computational analysis of the coherent electronic transmission through MAC nanofragments in search of defining characteristics. Our analysis, relying on a semiempirical Hamiltonian (Pariser–Parr–Pople) and Landauer theory, showed that states near the Fermi energy (E_F) in MAC inherit partial characteristics of analogous surface states in graphene nanofragments. Away from E_F, current is carried by a set of delocalized states that transition into a subset of insulating interior states at the extreme portions of MAC’s energy spectrum. Finally, we also found that quantum interference between frontier orbitals is a common feature among MAC nanofragments.