Photoconductivity of single-wall carbon nanotubes under continuous-wave near-infrared illumination

The photoconductivity of films of single-wall carbon nanotubes has been studied under continuous-wave near-infrared illumination. The photocurrent exhibits a linear response with the light intensity and with bias voltage up to 5 V. The temporal photoresponse of on/off step illumination shows a relatively slow relaxation time (4.3 s for films with a thickness of similar to500 nm), which can be interpreted in terms of a kinetic model that takes into account the binding of photoelectrons with adsorbed oxygen. Possible applications of this photosensitive material are discussed. (C) 2003 American Institute of Physics.