Transport properties of carbon nanotubes with odd-numbered carbon rings

We present our results of an accurate and detailed study of the structural and transport properties of the recently proposed Haeckelite carbon nanotubes (HCNs) using the generalized tight-binding molecular dynamics scheme. The quantum conductance and the current vs voltage $\left(I\text{−}V\right)$ curves for the HCNs were calculated using two independent methods: (i) an embedded form of the surface Green’s function matching method and (ii) the Bardeen’s transfer Hamiltonian approximation. The $I\text{−}V$ characteristics thus obtained are compared with the corresponding ones of single-wall carbon nanotubes (SWCNs) of the same diameter and length. Our results indicate that, although infinite HCNs were reported to have many conduction channels compared to the SWCNs, contrary to expectations their conductivity under a given bias configuration is comparable to that of the SWCNs.

Figure 1

The fully relaxed graphene sheets for the three types of Haeckelites. They consist of $R_{5,7}$, $H_{5,6,7}$, and $O_{5,6,7}$ structures. Left and right panels show top and side views, respectively.

Figure 2

The relaxed Haeckelite nanotubes obtained from rolling up the structures in Fig. 1. The nanotubes are denoted by $R_{5,7}(0,4)$, $H_{5,6,7}(4,0)$, and $O_{5,6,7}(0,4)$.

Figure 3

(Color online) $I\text{−}V$ curves for the Haeckelite nanotubes along with those for the SWCNs. The inset shows the DOS. The Fermi level is shifted at zero energy.

Figure 4

(Color online) The transmission functions $T\left(E\right)$ (in units of $e^2∕h$) for the studied nanotubes as indicated in the legend. The Fermi energy is located at zero energy.