IBM has created an electrically-controlled, single-molecule light emitter using carbon nanotubes. Researchers at IBM engineered a carbon nanotube to be "ambipolar", so they could simultaneously inject negative charges (electrons) from a source electrode and positive charges (holes) from a drain electrode into a single carbon nanotube. When the electrons and holes meet in the nanotube, they neutralize each other and generate light. The researchers detected light with a wavelength of 1.5 micrometers, which is used in optical communications. The development is expected to spur further research in the use of carbon nanotubes in nanoscale electronic and photonic devices.
http://www.research.ibm.com/pics/nanotech/
- Positive and negative charges are simultaneously injected into a carbon nanotube through the source and drain electrodes at its two ends to generate light with a wavelength of 1.5 micrometers. Source: IBM
