IR emission from Schottky barrier carbon nanotube FETs

Single-walled carbon nanotubes (SWNTs) are tubular 1D nanostructures made of /spl pi/ conjugated C-C bonds. The nanotube band structure consists of unique sets of 1D subbands resulting in sharp peaks in the density of states (DOS). These DOS lead to strong optical interband transitions as observed in recent absorption and emission experiments. Here, we present a novel electroluminescence device based on ambipolar carbon nanotube FETs. The device enables efficient charge injection across the metal-nanotube contact barrier and the band gap recombination of carriers in the nanotube with an emission in the near IR. To our knowledge, this nanotube device represents the smallest electrically pumped optical emission source. It also opens up new possibilities for fundamental study of electron-hole interactions in 1D and in both electronics and optoelectronics.