title: Up-conversion fluorescence: noncoherent excitation by sunlight.
abstract: We demonstrate up-conversion of noncoherent sunlight realized by ultralow excitation intensity. The bimolecular up-conversion process in our systems relies on the presence of a metastable triplet excited state, and thus has dramatically different photophysical characteristics relative to the other known methods for photon up-conversion (two-photon absorption, parametric processes, second harmonic generation, sequential multiphoton absorption, etc.).
authors.affiliation: Max-Planck-Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany. balouche@mpip-mainz.mpg.de
authors.forename: S
authors.initials: S
authors.lastname: Baluschev
authors.forename: T
authors.initials: T
authors.lastname: Miteva
authors.forename: V
authors.initials: V
authors.lastname: Yakutkin
authors.forename: G
authors.initials: G
authors.lastname: Nelles
authors.forename: A
authors.initials: A
authors.lastname: Yasuda
authors.forename: G
authors.initials: G
authors.lastname: Wegner