Electrical transport properties of intramolecular p-n-p junctions formed on individual semiconducting carbon nanotubes are reported. Chemical dopant 'profiling' along the length of a nanotube divides the nanotube into two p-doped sections and a central n-doped section. The double p-n junctions formed on the nanotube dictate the electrical characteristics of the system. Well-defined and highly reproducible single-electron transistors with much smaller size than the geometrical length of the nanotube are obtained.
Chemistry Department, Stanford University
Stanford, CA 94305 USA