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

- All of the simulated CNT structures show the negative differential resistance (NDR) property.
- The results show that the tunnelling current, number of NDR peaks and conductance depends upon the level of doping.
- The two atom chromium doped SWCNT device shows a higher peak to valley current ratio than the 4 atom or 6 atom doped SWCNT.
- All of the results are compared with the previously reported results in the subject.
- The observed results are of great importance for the modelling and simulation of CNT devices and their applications.

AbstrctThis 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.