title: Single molecule modulation spectroscopy of conjugated polymers.
abstract: This paper describes a new single molecule spectroscopy approach for the investigation of triplet-triplet and singlet-triplet interactions in conjugated polymers. The technique involves the irradiation of isolated single, mulitchromophoric, conjugated polymer molecules by a repetitive sequence of variable-intensity microsecond time scale excitation pulses. The fluorescence intensity is synchronously time-averaged for thousands of cycles of the pulse sequence to yield a high signal-to-noise fluorescence transient on the microsecond time scale. The transient can be analyzed with kinetic models to obtain quantitative information about the kinetics of triplet-triplet exciton annihilation and the quenching of singlet excitons by triplet excitons in conjugated polymers.
authors.affiliation: Center for Nano- and Molecular Science and Technology and Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712, USA.
authors.forename: Andre J
authors.initials: AJ
authors.lastname: Gesquiere
authors.forename: Young Jong
authors.initials: YJ
authors.lastname: Lee
authors.forename: Ji
authors.initials: J
authors.lastname: Yu
authors.forename: Paul F
authors.initials: PF
authors.lastname: Barbara