ABSTRACT
Figure 10.8 Temperature dependencies of the resistivity calculated for armchair and zigzag SWCNTs. In Figure 10.9, we show the temperature dependencies of the resistances for a m-SWCNT, which are hole doped by applying gate voltages (Vg) of –10 V and 2 V, respectively. The diameter d of the tube is about 1.5 nm and the length L is about 200 nm. The data are taken from [Kong et al. (2001)]. In both doping levels, the resistance does not increase linearly with temperature. Instead, the temperature dependencies can be well fitted (solid lines) by the equation: R(T) = R0 + ATp. The best fit yields p = 1.58 ± 0.12 and 2.30 ± 0.18 for Vg = –10 V and 2 V, respectively. The temperature dependencies are incompatible with the parameter-free calculation (Figure 10.8). The values of the exponent p in both cases are well off from the theoretical value of about 1. Using L = 200 nm, the temperature dependent resistivity at room temperature rT(300K) is calculated to be 74.2 kW/mm at Vg = 2 V and 19.3 kW/mm at Vg = –10 V. These resistivity values are significantly larger than the theoretically predicted value of about 10 kW/mm.
