Field emission from cylindrical carbon nanotube cathodes: Possibilities for luminescent tubes

We show that the field of application of cold electron film emitters can be extended to nonplanar geometries by demonstrating a cylindrical field emission diode. The cathode is a metallic wire on which multiwall carbon nanotubes are grown by the catalytic decomposition of acetylene over a Fe catalyst. The emitter shows excellent performances and can be used to realize a luminescent, mercury-free, tube.