title: Quantum efficiency and capture cross section of first and second excitonic transitions of single-walled carbon nanotubes measured through photoconductivity.
abstract: Comparing photoconductivity measurements, using p-n diodes formed along individual single-walled carbon nanotubes (SWNT), with modeling results, allows determination of the quantum efficiency, optical capture cross section, and oscillator strength of the first (E11) and second (E22) excitonic transitions of SWNTs. This is in the infrared region of the spectrum, where little experimental work on SWNT optical absorption has been reported to date. We estimate quantum efficiency (η) ~1-5% and provide a correlation of η, capture cross section, and oscillator strength for E11 and E22 with nanotube diameter. This study uses the spectral weight of the exciton resonances as the determining parameter in optical measurements.
authors.affiliation: College of Nanoscale Science and Engineering, University at Albany, State University of New York, Albany, New York 12203, United States.
authors.forename: Argyrios
authors.initials: A
authors.lastname: Malapanis
authors.forename: Vasili
authors.initials: V
authors.lastname: Perebeinos
authors.forename: Dhiraj Prasad
authors.initials: DP
authors.lastname: Sinha
authors.forename: Everett
authors.initials: E
authors.lastname: Comfort
authors.forename: Ji Ung
authors.initials: JU
authors.lastname: Lee