nanotubes 66 a heat source 68 is provided for heating the oven 56 to generate a temperature gradient permitting rapid condensation of the atoms or molecules of carbon and the atoms of metal catalyst a heat resistant tubular member 70 having a plasma receiving end 72 extends through the oven 56 the plasma receiving end 72 being disposed upstream of the plasma discharging end 54 of the plasma tube 52 the apparatus further includes a gas injector 74 for injecting a cooling inert gas into the tubular member 70 downstream of the secondary plasma 64 the cooling inert gas assists in providing the temperature gradient the deposit of single wall carbon nanotubes 66 occurs on the heat resistant tubular member 70 upstream and downstream of the oven 56 the inert gas flows through the plasma tube 52 along a helical path represented by the arrow 76 similarly the carbon containing gas and the metal catalyst optionally in admixture with a carrier gas flow through the conduit 60 along a helical path represented by the arrow 78 the metal catalyst which is fed through the conduit 60 can be either an organometallic complex such as ferrocene or an inorganic metal catalyst such as iron instead of feeding the metal catalyst through the conduit 60 it is possible to feed only the carbon containing gas through the conduit 60 and to feed the metal catalyst in admixture with the inert gas through the plasma tube 52 in such a case the metal catalyst must be an inorganic metal catalyst to prevent undesirable formation of carbon.