title: Field-enhanced photocurrent spectroscopy of excitonic states in single-wall carbon nanotubes.
abstract: Excitonic and free-carrier transitions in single-wall carbon nanotubes are distinguished using field-enhanced photocurrent spectroscopy. Electric field dissociation allows for the detection of bound-exciton states that otherwise would not contribute to the photocurrent. Excitonic states associated with both the ground-state semiconductor and the ground-state metallic nanotube transitions are resolved. The observation of a metallic excitonic state corroborates recent predictions of a symmetry gap existing in metallic nanotubes.
authors.affiliation: Department of Electrical and Computer Engineering, University of Louisville, Kentucky 40292, USA.
authors.forename: Aditya
authors.initials: A
authors.lastname: Mohite
authors.forename: Ji-Tzuoh
authors.initials: JT
authors.lastname: Lin
authors.forename: Gamini
authors.initials: G
authors.lastname: Sumanasekera
authors.forename: Bruce W
authors.initials: BW
authors.lastname: Alphenaar
mesh_terms: D046529:Microscopy, Electron, Transmission; D037742:Nanotubes, Carbon; D010777:Photochemistry; D055585:Physical Phenomena; D010825:Physics; D013059:Spectrum Analysis, Raman
chemical_list: D037742:Nanotubes, Carbon