title: Optical sensing of current dynamics in organic light-emitting devices at the nanometer scale.
abstract: Photoluminescence quenching of single dibenzoterrylene (DBT) dye molecules in a polymeric organic light-emitting diode was utilized to analyze the current dynamics at nanometer resolution. The quenching mechanism of single DBT molecules results from an increase in the triplet-state population induced by charge carrier recombination on individual guest molecules. As a consequence of the long triplet-state relaxation time, its population results in a reduced photoluminescence of the dispersed fluorescent dyes. From the decrease in photoluminescence together with photon correlation measurements, we could quantify the local current density and its time-dependent evolution in the vicinity of the single-molecule probe. This optical technique establishes a non-invasive approach to map the time-resolved current density in organic light-emitting diodes on the nanometer scale.
authors.affiliation: 3rd Physics Institute and Research Center SCoPE, University of Stuttgart, Germany.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Nothaft
authors.forename: Steffen
authors.initials: S
authors.lastname: Höhla
authors.forename: Aurélien
authors.initials: A
authors.lastname: Nicolet
authors.forename: Fedor
authors.initials: F
authors.lastname: Jelezko
authors.forename: Norbert
authors.initials: N
authors.lastname: Frühauf
authors.forename: Jens
authors.initials: J
authors.lastname: Pflaum
authors.forename: Jörg
authors.initials: J
authors.lastname: Wrachtrup