Electronic properties of aligned carbon nanotubes

The electronic properties of aligned carbon nanotube films have been investigated by conduction electron spin resonance (CESR) and transport measurements. Hall effect and CESR reveal that the nanotubes behave like a semimetal with 1019 carriers/cm3 at room temperature. The intrinsic resistivity is an order of magnitude lower than the dc resistivity of the films. Strong deviations in the physical characteristics suggest a charge-carrier localisation below 40 K. Low level of doping with Potassium strongly modifies the electronic properties of the nanotubes.