Investigation of superconductivity in the single-walled carbon nanotubes

Superconductivity in the single-walled carbon nanotubes is investigated. First, effect of diameter increasing on the clean systems critical temperature, TcTc, is calculated. Then effect of impurity doping on the reduction of critical temperature TcTc, of single-walled carbon nanotubes, is discussed. Our calculations illustrate that metallic zigzag single-walled carbon nanotubes have higher TcTc than armchair single-walled carbon nanotubes with approximately same diameters and TcTc decreases by increasing diameter. This can explain why superconductivity could be found in the small diameter single-walled carbon nanotubes. We found for the impurity doped systems, impurity in the strong scattering regime can decrease TcTc significantly while in the weak scattering regime TcTc is not affected by impurity doping.