title: Unique origin of colors of armchair carbon nanotubes.
abstract: The colors of suspended metallic colloidal particles are determined by their size-dependent plasma resonance, while those of semiconducting colloidal particles are determined by their size-dependent band gap. Here, we present a novel case for armchair carbon nanotubes, suspended in aqueous medium, for which the color depends on their size-dependent excitonic resonance, even though the individual particles are metallic. We observe distinct colors of a series of armchair-enriched nanotube suspensions, highlighting the unique coloration mechanism of these one-dimensional metals.
authors.affiliation: Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, United States.
authors.forename: Erik H
authors.initials: EH
authors.lastname: Hároz
authors.forename: Juan G
authors.initials: JG
authors.lastname: Duque
authors.forename: Benjamin Y
authors.initials: BY
authors.lastname: Lu
authors.forename: Pavel
authors.initials: P
authors.lastname: Nikolaev
authors.forename: Sivaram
authors.initials: S
authors.lastname: Arepalli
authors.forename: Robert H
authors.initials: RH
authors.lastname: Hauge
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Doorn
authors.forename: Junichiro
authors.initials: J
authors.lastname: Kono