Title :
Ultrafast hot exciton dissociation at organic interfaces
Author :
Maiuri, Margherita ; Grancini, Giulia ; Fazzi, D. ; Petrozza, Anna Maria ; Brida, Daniele ; Cerullo, Giulio ; Lanzani, Guglielmo
Author_Institution :
Dipt. di Fis., Politec. di Milano, Milan, Italy
Abstract :
Here, we monitor the exciton dissociation process in a low-band gap polymer: fullerene (PCPDTBT:PCBM) blend combining ultrafast transient absorption spectroscopy with sub-15 fs time resolution with high level quantum chemical calculations. We find that exciton dissociation leads to both bound interfacial charge transfer states and free polarons within a time scale of 20-50 fs, with a branching ratio that depends on the excess energy.
Keywords :
charge transfer states; excitons; fullerene compounds; high-speed optical techniques; polarons; polymer blends; PCPDTBT-PCBM blend; branching ratio; free polarons; high level quantum chemical calculations; interfacial charge transfer states; low-band gap polymer-fullerene blend; organic interfaces; time 20 fs to 50 fs; ultrafast hot exciton dissociation; ultrafast transient absorption spectroscopy; Absorption; Excitons; Photonics; Photovoltaic cells; Photovoltaic systems; Polymers;
Conference_Titel :
Lasers and Electro-Optics Europe (CLEO EUROPE/IQEC), 2013 Conference on and International Quantum Electronics Conference
Conference_Location :
Munich
Print_ISBN :
978-1-4799-0593-5
DOI :
10.1109/CLEOE-IQEC.2013.6801042
