Regensburg 2019 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 29: Two-dimensional Materials II: graphene (joint session HL/CPP)
CPP 29.4: Vortrag
Dienstag, 2. April 2019, 14:45–15:00, H36
How Laser-induced defects modify optical properties of semiconducting Armchair Graphene Nanoribbons — •Seyed Khalil Alavi1,2, Boris V. Senkovskiy3, Markus Pfeiffer1, Danny Haberer4, Felix R. Fischer4, Alexander Grüneis3, and Klas Lindfors1 — 1Department of Chemistry, Universität zu Köln, Luxemburger Str. 116, 50939 Köln, Germany — 2Institut für Angewandte Physik der Universität Bonn, Wegeler Strasse 8, 53115 Bonn, Germany — 3II. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, 50937 Köln, Germany — 4Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
Armchair graphene nanoribbons (AGNRs) with tunable band gap are promising candidate for optoelectronic devices. We have earlier shown how photoluminescence emission is boosted via formation of laser-induced defects in AGNRs lattices [1]. Here we probe the origin of this modification by measuring the extinction spectrum of a layer of AGNRs. Our results show that there are two pronounced peaks at approximately 2.4 and 1.8 eV in the spectrum of pristine GNRs. The latter peak energetically coincides with emission feature. This peak surprisingly disappears from the extinction spectrum after defects formation. We thus attribute the 1.8 eV peak to a quenching state. We additionally extract the absolute absorbance of AGNRs and find that it is a factor of three higher than graphene absorbance in visible range. [1] B. V. Senkovskiy, M. Pfeiffer, S. K. Alavi, et al., Nano Lett. 17, 4029-4037, 2017.