Doping-free carbon nanotube optoelectronic devices

Semiconducting carbon nanotubes (CNTs) possess outstanding electrical and optical properties because of their special one-dimensional (1D) structure. CNTs are direct bandgap materials, which makes them ideal for use in optoelectronic devices, e. g. light emitters and light detectors. Excitons determine their light absorption and light emission processes due to the strong Coulomb interactions between electrons and holes in CNTs. In this paper, we review recent progress in CNT photodetectors, photovoltaic devices and light emitters. In particular, we focus on the doping-free CNT optoelectronic devices developed by our group in recent years.