Dresden 2014 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 109: Ultra-fast phenomena I
HL 109.3: Talk
Friday, April 4, 2014, 10:00–10:15, POT 006
Long-Lived Electronic 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 Strüber3, 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 in optically pumped (400 nm excitation) molecular states of the metalorganic complex tris(8-hydroxyquinolinato)aluminium (Alq3) deposited on cobalt is investigated by coherent two-dimensional nanoscopy [1]. Upon excitation with sequences of ultrashort pulses at 800 nm quantum beats appear in the time-resolved photoemission signal. In two-dimensional nanoscopy spectra two excited electronic states are identified with an energy spacing of about 77 meV. Their linewidth are 11 meV and 48 meV, respectively, corresponding to coherence lifetimes of about 370 fs and 87 fs. The appearance of such narrow spectral features indicates that electronic excitations in an individual adsorbate state can be surprisingly long and thus can play an important role in determining charge transfer efficiencies at the metal-hybrid interface.
[1] Aeschlimann et al. Science 333, 1723-1726, (2011)