Boron/nitrogen pairs Co-doping in metallic carbon nanotubes:a first-principle study

By using the first-principles calculations,the electronic structure and quantum transport properties of metallic carbon nanotubes with B/N pairs co-doping have been investigated.It is shown that the total energies of metallic carbon nanotubes are sensitive to the doping sites of the B/N pairs.The energy gaps of the doped metallic carbon nanotubes decrease with decreasing the concentration of the B/N pair not only along the tube axis but also around the tube.Moreover,the I-V characteristics and transmissions of the doped tubes are studied.Our results reveal that the conducting ability of the doped tube decreases with increasing the concentrations of the B/N pairs due to symmetry breaking of the system.This fact opens a new way to modulate band structures of metallic carbon nanotubes by doping B/N pair with suitable concentration and the novel characteristics are potentially useful in future applications.