Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 23: Plasmonics and Nanooptics: Light-Matter Interaction, Spectroscopy
O 23.16: Poster
Monday, March 7, 2016, 18:15–20:30, Poster E
Long-lived coherence in the metal-organic hybrid Cobalt/Alq3 — Martin Aeschlimann1, Tobias Brixner2, Mirko Cinchetti1, Norman Haag1, Matthias Hensen3, •Bernhard Huber2, Christian Kramer2, Walter Pfeiffer3, Martin Piecuch1, Christian Schneider1, Benjamin Stadtmüller1, and Philip Thielen1 — 1Fachbereich Physik and Research Center OPTIMAS, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern, Germany — 2Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany — 3Fakultät für Physik, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
The coherent electron dynamics of optically pumped (400 nm) molecular states of the metal-organic complex tris(8-hydroxyquinolinato)aluminium (Alq3) deposited on Cobalt are investigated with time-resolved photoemission microscopy (PEEM). We observe a coherence signal in interferometric autocorrelation traces when probing the excited-state manifold of Alq3 with 800 nm laser pulses. In two-dimensional (2D) nanoscopy spectra, two excited states are identified with an energy spacing of about 77 meV with respective linewidths of 11 meV and 48 meV. Measuring the kinetic energy of the photoelectrons, these features prevail over the entire accessible energy range of about 1 eV. The observed signal can be explained by long-lived coherent excited states of the adsorbate that decay among others via coupling to excited electrons in the substrate giving rise to a photoemission signal that depends linearly on the laser intensity.