UNRAVELING NANOTUBES - FIELD-EMISSION FROM AN ATOMIC WIRE

Field emission of electrons from individually mounted carbon nanotubes has been found to be dramatically enhanced when the nanotube tips are opened by laser evaporation or oxidative etching. Emission currents o f 0.1 to 1 microampere were readily obtained at room temperature with bias voltages of less than 80 volts, The emitting structures are concl uded to be linear chains of carbon atoms, C-n (n = 10 to 100), pulled out from the open edges of the graphene wall layers of the nanotube by the force of the electric field, in a process that resembles unraveli ng the sleeve of a sweater.