Quantum transport properties of carbon nanotube with topologic defects

¹ College of Physics and Microelectronic Science, Hunan University, Changsha 410082, P.R. China
² College of Materials Science and Engineering, Hunan University, Changsha 410082, P.R. China

Corresponding author: guf66958@hnu.edu.cn

Received: 14 February 2008
Accepted: 26 March 2008
Published online: 30 May 2008

Abstract

Using the density-functional theory (DFT) combining non-equilibrium Green's function (NEGF) technique, we have studied the electronic transport properties of (7,0)-(8,0), (8,0)-(9,0) and (8,0)-(10,0) single-walled carbon nanotube heterojunctions which contain a pentagon-heptagon (5/7) pair of defect, a pentagon-heptagon (5/7) pair of defect and a pentagon-hexagon-heptagon (5/6/7) topological defect, respectively. Our calculations indicate that the 5/6/7 defect has greater effect on the electronic transport properties than that of the isolated 5/7 defect because there exist three weakly localized states in (8,0)-(10,0) heterojunction while two in (7,0)-(8,0) heterojunction. Furthermore, there appears to be negative differential resistance (NDR) in the semiconductor-metal (8,0)-(9,0) heterojunction in small bias region due to the suppression of conduction channel.