NANOTUBE NANODEVICE

A scanning tunneling microscope (STM) was used to explore the local el ectrical characteristics of single-wall carbon nanotubes. As the STM t ip was moved along the length oi the nanotubes, well-defined positions were found where the transport current changes abruptly from a graphi tic-like response to one that is highly nonlinear and asymmetrical, in cluding near-perfect rectification. The observations are consistent wi th the existence of localized, on-tube nanodevices of a type proposed theoretically.