SurfaceScience21 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 24: Poster Session II: Plasmonics and nanooptics II
O 24.2: Poster
Montag, 1. März 2021, 13:30–15:30, P
Particle Plasmon Induced Electronic Excitations on Silicon and Tetracene Crystals — •Katharina Engster1,2, Kevin Oldenburg2, Chris Rehhagen1,2, Stefan Lochbrunner1,2, Karl-Heinz Meiwes-Broer1,2, Sylvia Speller1,2, and Ingo Barke1,2 — 1Institut für Physik, Universität Rostock, Germany — 2Department Leben-Licht-Materie, Universität Rostock, Germany
Utilizing plasmonics of metal nanoparticles to locally excite organic semiconductors is promising with respect to transfer energy from a defined starting point over longer distances. Two-photon photoemission electron microscopy (2P-PEEM) enables observation of near-fields with high lateral resolution due to the increased photoemission yield. With excitation spectroscopy we show that the particles can be addressed individually by their distinct plasmonic properties [1]. This results in an enhanced excitation of both, the substrate and nearby organic structures. The coupling to the substrate was studied by analyzing the occurring surface photovoltage (SPV) on Si(100)-(2x1). The distance dependence from the particles reveals an enhanced plasmon induced charge carrier density in the vicinity of the nanoparticles. For tetracene nanostructures we observe a plasmonically assisted local triplet exciton density. We do not observe clear migration in these small structures, which we attribute to inhomogeneities of the molecule aggregate [2]. Therefore, we present first measurements on larger, solution grown tetracene microcrystals.
[1] K. Oldenburg et al., J. Phys. Chem. C 123 (2019).
[2] G. M. Akselrod et al., Nat. Commun. 5 (2014).