Effect of doping on the transport properties of single-walled carbon nanotube two probe systems

Abstract

This paper reports the doping induced negative differential resistance (NDR) in chromium substituted zig-zag (4, 0) single walled carbon nanotube (SWCNT) devices and the effect of the doping level on this property by using non-equilibrium Green's function theory formalism in combination with semi-empirical extended Huckel theory (EHT) calculations of the Atomistic Tool Kit software in device mode. The results show that the tunneling current, number of NDR peaks and the conductance increases with an increase in the level of doping. The high peak to valley current ratio (PVR) of the three proposed models are presented in the form of tables for comparative studies. The highest peak to valley current ratio of 5.70 is found in the two atom chromium doped SWCNT geometry. It is believed that the explored chromium doped CNT devices in this study will find number of applications in the future, particularly for fast switching and high speed signal processing.