title: Tracing Single Electrons in a Disordered Polymer Film at Room Temperature.
abstract: The transport of charges lies at the heart of essentially all modern (opto-) electronic devices. Although inorganic semiconductors built the basis for current technologies, organic materials have become increasingly important in recent years. However, organic matter is often highly disordered, which directly impacts the charge carrier dynamics. To understand and optimize device performance, detailed knowledge of the transport mechanisms of charge carriers in disordered matter is therefore of crucial importance. Here we report on the observation of the motion of single electrons within a disordered polymer film at room temperature, using single organic chromophores as probe molecules. The migration of a single electron gives rise to a varying electric field in its vicinity, which is registered via a shift of the emission spectra (Stark shift) of a chromophore. The spectral shifts allow us to determine the electron mobility and reveal for each nanoenvironment a distinct number of different possible electron-transfer pathways within the rugged energy landscape of the disordered polymer matrix.
authors.affiliation: Experimental Physics IV and Bayreuth Institute for Macromolecular Research (BIMF), University of Bayreuth , 95440 Bayreuth, Germany.
authors.forename: Kevin
authors.initials: K
authors.lastname: Wilma
authors.affiliation: Experimental Physics IV and Bayreuth Institute for Macromolecular Research (BIMF), University of Bayreuth , 95440 Bayreuth, Germany.
authors.forename: Abey
authors.initials: A
authors.lastname: Issac
authors.affiliation: Institut für Organische Chemie and Center for Nanosystems Chemistry, Universität Würzburg , Am Hubland, 97074 Würzburg, Germany.
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Institut für Organische Chemie and Center for Nanosystems Chemistry, Universität Würzburg , Am Hubland, 97074 Würzburg, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Würthner
authors.affiliation: Experimental Physics IV and Bayreuth Institute for Macromolecular Research (BIMF), University of Bayreuth , 95440 Bayreuth, Germany.
authors.forename: Richard
authors.initials: R
authors.lastname: Hildner
authors.affiliation: Experimental Physics IV and Bayreuth Institute for Macromolecular Research (BIMF), University of Bayreuth , 95440 Bayreuth, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Köhler