Conductance modulation in graphene nanoribbon under transver-se asymmetric electric potential

We theoretically study the effect of transverse electric potentials on the transport properties of armchair graphene nanoribbons (AGNRs), formed by pairs of asymme-tric gates placed along the side of the ribbon. Single pair and dual pair configurations are considered. We also examine the effect of hollows (spatial regions void of carbon atoms) in the AGNR channels. We find that the use of hollowed AGNRs in the dual pair configuration allows for a significant modulation of the transport gap, when the two pairs have opposite polarity of gate bias. Furthermore, we show that for the dual-gate system, hollowed AGNR channels exhibit the optimal ratio of ON-state to OFF-state conductance, due to the smaller OFF-state conductance compared with spatially homogenous AGNR channels. Our results indicate that transverse gate technology coupled with careful engineering of hollow geometry may lead to possible applications in graphene-based electronic devices.