Altering regularities of electronic transport properties in twisted graphene nanoribbons

Based on density-function theory combined with nonequilibrium Green's function method, the electronic transport properties of twisted armchair- and zigzag-edge graphene nanoribbons (AGNRs and ZGNRs) are investigated. Results show that electronic transport properties are sensitive to twisting deformations for semiconductor-type AGNRs, but are robust against twisting deformations for quasi-metallic AGNRs and ZGNRs. The electronic conduction becomes weaker gradually for moderate-gap semiconductor-type AGNRs, but gets stronger for wide-gap semiconductor-type AGNRs when the twisted angle increases to 120 degrees. While for quasi-metallic AGNRs and ZGNRs, the electronic conduction is strong and obeys Ohm's law of resistance strictly. Mechanisms for such results are suggested. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4733618]