Dresden 2009 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
O: Fachverband Oberflächenphysik
O 46: Time-resolved spectroscopies I
O 46.2: Talk
Thursday, March 26, 2009, 10:45–11:00, SCH A315
Freezing Hot Electrons in Crystalline NH3 and D2O on Metal Surfaces — •Julia Stähler1,2, Michael Meyer1, Uwe Bovensiepen1, Cornelius Gahl3, and Martin Wolf1,4 — 1Freie Universität Berlin, Fachbereich Physik, Arnimallee 14, 14195 Berlin — 2University of Oxford, Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom — 3Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Str. 2A, 12489 Berlin — 4Fritz-Haber-Institut der MPG, Abteilung Physikalische Chemie, Faradayweg 4-6, 14195 Berlin
Electron transfer across molecule-metal interfaces is crucial in technologically highly relevant fields as, for instance, the design of nanoscale electronic devices and solar cells. Knowledge of the impact of the molecular structure and morphology on the interfacial electron dynamics is hereby essential for the development of efficient and reliable appliances. We use time-resolved two-photon photoelectron (2PPE) spectroscopy to study the electron transfer and solvation dynamics at the NH3/Cu(111) and the D2O/Ru(001) interface. We show that (i) the electron dynamics are significantly influenced by crystallization of the adlayer, (ii) the structural reorganization results in electron lifetimes on the order of minutes, and (iii) the microscopic and structural properties of the solvent determine the energetic relaxation even on macroscopic timescales. In addition, we present the first direct observation of electron trapping in pre-existing traps and demonstrate that the remarkably long lifetimes cannot be attributed to a purely morphological transition.