Dynamical behavior of copper atoms in a carbon nanotube channel

The transportation of copper atoms along a carbon nanotube (CNT) channel, which consists of a junction, is studied using molecular dynamics simulations. A bias voltage is applied along the channel to induce an electromigration force on copper atoms. The study focuses on the flow of copper atoms by varying the voltage gradient and the temperature of copper. The results show that the temperature increase due to electromigration forces is lower when the initial temperature of copper is higher. A higher temperature results in larger thermal vibrations of copper atoms, which partly contributes to a change in the atomic arrangement of copper when copper is transported along the channel. This change occurs due to the existence of the CNT channel junction. Besides this, the interactive forces between copper and the CNT channel are significant when copper is approaching the junction. The effect of temperature on the interactive forces at the junction of the channel is more prominent than the effect of electromigration forces. The resistive forces on copper produced by the CNT channel are quite insignificant for a straight channel, but are more prominent when copper is flowing against the obstruction of the CNT channel junction. (C) 2010 Elsevier Ltd. All rights reserved.