Two- to one-dimensional crossover in graphene quantum dot arrays observed in reduced graphene oxide nanoribbons

We investigate how the electron transport properties of graphene quantum dot (GQD) arrays transition from two dimensions (2D) to one dimension (1D) in lithographically defined reduced graphene oxide nanoribbons (RGONRs). From the low-temperature electron transport measurements of 200-, 100-, and 50-nm-wide RGONRs, we find that the energy barrier for charge transport increases with decreasing RGONR width in both the Coulomb blockade and the variable-range hopping regime. Different charge transport parameters for 200-nm RGONR are in agreement with 2D transport while these parameters show a gradual transition to 1D transport in 50-nm RGONR.