Enhancement of semiconducting single-wall carbon-nanotube photoluminescence

Photoluminescence properties of semiconducting single-wall carbon-nanotube (s-SWNT) thin films with different metallic single-wall carbon-nanotube (m-SWNT) concentrations are reported. s-SWNT purified samples are obtained by polymer-assisted selective extraction. We show that the presence of a few m-SWNTs in the sample generates a drastic quenching of the emission. Therefore, the highly purified s-SWNT film is a strongly luminescent material and a good candidate for future applications in photonics, such as near-IR emitters, modulators, and detectors.