Transport properties of a potassium-doped single-wall carbon nanotube rope

Four-probe resistance vs temperature and gate voltage are reported for an individual single-wall carbon nanotube rope before and after doping in situ with potassium. All the features in R(T) from unoriented bulk material, before and after doping, are qualitatively reproduced by the rope data. The 5.3 It conductance of the pristine rope decreases with positive gate voltage, while G vs V-g becomes featureless after K doping.