Ab initio study of Ti-contacted single-walled carbon nanotube

We have studied the electron-transport properties of Ti-contacted single-walled carbon nanotube (SWNT) using first-principles methods. Our calculations show that Ti has higher affinity for carbide formation and lower diffusion rate than other metals. If it is used as the electrodes of the metallic SWNT’s, two units of quantum conductance ${G=2G}_0{=4e}^2/h$ can be obtained. More importantly, gate voltages greatly affect the transport properties of SWNT’s. By adjusting the gate voltage, various functions can be achieved from the molecular devices composed of SWNT’s.