Erlangen 2022 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MO: Fachverband Molekülphysik
MO 9: Femtosecond Spectroscopy II
MO 9.4: Talk
Wednesday, March 16, 2022, 11:15–11:30, MO-H5
Tracking Ultrafast Exciton Diffusion in Squaraine Polymers at Various Temperatures — •Simon Büttner1, Julian Lüttig1, Pavel Malý1,2, Arthur Turkin3, Christoph Lambert3, and Tobias Brixner1 — 1Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany — 2Faculty of Mathematics and Physics, Charles University, Ke Karrlovu 5, 121 16 Praque, Czech Republic — 3Institut für Organsiche Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
Exciton diffusion is an important process in solar light harvesting and organic electronics. We use exciton–exciton-interaction two-dimensional (EEI2D) spectroscopy [1], which observes the process of exciton–exciton annihilation (EEA) to track the exciton diffusion in organic materials. Using EEI2D spectroscopy, we recently found in squaraine polymers a change from wavelike transport to a sub-diffusive character of exciton diffusion on an ultrafast timescale [2]. For further investigations we now analyzed the influence of the environment on exciton diffusion. We embedded the squaraine polymers in a polystyrene matrix and used EEI2D spectroscopy in a cryostat to determine the effect of temperature on exciton diffusion. We also compare the results with temperature-dependent measurements on squaraine polymers in solution to demonstrate the differences between a solid and a liquid environment.
[1] J. Dostál et al., Nat. Commun. 9, 2519, (2018)
[2] P. Malý et al., Chem. Sci. 11, 456 (2020)