Energy gap in graphene and silicene nanoribbons: A semiclassical approach

Abstract

We present a semiclassical approach based on recently reported Fermi velocity either graphene [1] and silicene [2] to explore the energy gap and band dispersion when graphene (silicene) is laterally confining at nanometer size, i.e., graphene nanoribbons (GNRs) and silicene nanoribbons (SiNRs). The modeling approach matches previous experimental and theoretical works for GNRs featuring widths ranging from 1 to 20 nm. Furthermore, the proposed approach results coherent with experimental measures on GNRs up to 100 nm wide. For this reason, we extend the modeling approach to SiNRs. A remarkable feature, in SiNRs, is an energy gap opening which is lower concerning GNRs due to a reduced Fermi velocity in silicene. SiNRs are expected to be a good competitor with GNRs for digital electronics.