
Microscopic wires of the future could be made from carbon nanotubes--rolled-up sheets of graphite only angstroms in diameter. Nanotubes could also be made into electronic devices like diodes and transistors, which are traditionally made from junctions of two or more semiconductors having different electrical properties. In the21 June PRL a team reports their calculations of the basic current and voltage relationships for nanotube junctions, showing that nanotubes should indeed be useable for diodes and other electronic components, once the fabrication techniques improve.David Tománek of Michigan State University in East Lansing calls nanotubes "dream materials" for building tiny circuits: They're strong, nonreactive, tolerant of...