The metallic character of the electronic transport in both asymmetric and symmetric ZGNRs has been established: the current has a semiconductor behavior, with negative differential resistance (NDR) effect. Symmetric SW defect, as a most unfavorable SW defect type for electric conductance, remarkably reduces the current values, but does not change the character of conductivity in both the asymmetric and symmetric ZGNRs. NDR has been explained by the SW defect-induced alteration of the number of frontier molecular orbitals entering bias windows. | Communications in Physics, Vol. 28, No. 3 (2018), pp. 201-216 DOI: TUNING ELECTRONIC TRANSPORT PROPERTIES OF ZIGZAG GRAPHENE NANORIBBONS WITH STONE-WALES DEFECT NGUYEN THANH TIENa,† , BUI THAI HOCa , NGUYEN VAN UTa AND LE TUANb a College of Natural Sciences, Can Tho University 3-2 Road, Can Tho City, Vietnam b School of Engineering Physics, Hanoi University of Science and Technology 1 Dai Co Viet Road, Hanoi, Vietnam † E-mail: nttien@ Received 13 June 2018 Accepted for publication 14 August 2018 Published 31 August 2018 Abstract. Influences of the symmetric Stone-Wales (SW) defect on the electronic transport properties of the zigzag graphene nanoribbons (ZGNRs) have been studied using ab initio simulation based on the density functional theory (DFT) combined with non-equilibrium Green’s function (NEGF) technique. The calculated transmission spectra T (E) at various bias windows, device densities of states (DDOS), current characteristics as well as local density of states (LDOS) of the defective asymmetric and symmetric ZGNRs are presented in comparison with those for the pristine ZGNRs. The metallic character of the electronic transport in both asymmetric and symmetric ZGNRs has been established: the current has a semiconductor behavior, with negative differential resistance (NDR) effect. Symmetric SW defect, as a most unfavorable SW defect type for electric conductance, remarkably reduces the current values, but does not change the character of conductivity in both the asymmetric and symmetric ZGNRs. NDR has been explained by the SW defect-induced alteration of the number of frontier molecular orbitals entering bias windows. Keywords: density-functional theory, non-equilibrium, Green function, electronic transport, graphene nanoribbon, transmission spectrum, current-voltage characteristics. Classification numbers: ; ; . c 2018 Vietnam Academy of Science and Technology 202 TUNING ELECTRONIC .
