title: Exciton binding energy in semiconducting single-walled carbon nanotubes.
abstract: The exciton binding energy serves as a critical criterion for identification of the nature of elementary excitations (neutral excitons versus a pair of charged carriers) in semiconductor materials. An exciton binding energy of 0.41 eV is determined experimentally for a selected nanotube type, the (8,3) tube, confirming the excitonic nature of the elementary excitations. This determination is made from the energy difference between an electron-hole continuum and its precursor exciton. The electron-hole continuum results from dissociation of excitons following extremely rapid exciton-exciton annihilation and possibly also ultrafast relaxation from the second to the first exciton states and is characterized by distinct spectroscopic and dynamic signatures.
authors.forename: Ying-Zhong
authors.initials: YZ
authors.lastname: Ma
authors.forename: Leonas
authors.initials: L
authors.lastname: Valkunas
authors.forename: Sergei M
authors.initials: SM
authors.lastname: Bachilo
authors.forename: Graham R
authors.initials: GR
authors.lastname: Fleming