TY  - JOUR
A1  - Süß, Jasmin
A1  - Wehner, Johannes G.
A1  - Dostál, Jakub
A1  - Engel, Volker
A1  - Brixner, Tobias
T1  - Mapping of exciton-exciton annihilation in a molecular dimer via fifth-order femtosecond two-dimensional spectroscopy
JF  - Journal of Physical Chemistry Letters
N2  - We present a theoretical study on exciton–exciton annihilation (EEA) in a molecular dimer. This process is monitored using a fifth-order coherent two-dimensional (2D) spectroscopy as was recently proposed by Dostál et al. [Nat. Commun. 9, 2466 (2018)]. Using an electronic three-level system for each monomer, we analyze the different paths which contribute to the 2D spectrum. The spectrum is determined by two entangled relaxation processes, namely, the EEA and the direct relaxation of higher lying excited states. It is shown that the change of the spectrum as a function of a pulse delay can be linked directly to the presence of the EEA process.
KW  - exciton-exciton
KW  - Exziton
KW  - Spektroskopie
KW  - EEA
KW  - 2Dimensionale Spektroskopie
KW  - exciton
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-178420
UR  - https://aip.scitation.org/doi/full/10.1063/1.5086151
N1  - This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in J. Süß et al., J. Chem. Phys. 150, 104304 (2019); https://doi.org/10.1063/1.5086151 and may be found at https://doi.org/10.1063/1.5086151.
VL  - 150
IS  - 10
ER  - 
TY  - INPR
A1  - Süß, Jasmin
A1  - Wehner, Johannes G.
A1  - Dostál, Jakub
A1  - Engel, Volker
A1  - Brixner, Tobias
T1  - Mapping of exciton-exciton annihilation in a molecular dimer via fifth-order femtosecond two-dimensional spectroscopy
T2  - Journal of Physical Chemistry Letters
N2  - We present a theoretical study on exciton–exciton annihilation (EEA) in a molecular dimer. This process is monitored using a fifth-order coherent two-dimensional (2D) spectroscopy as was recently proposed by Dostál et al. [Nat. Commun. 9, 2466 (2018)]. Using an electronic three-level system for each monomer, we analyze the different paths which contribute to the 2D spectrum. The spectrum is determined by two entangled relaxation processes, namely, the EEA and the direct relaxation of higher lying excited states. It is shown that the change of the spectrum as a function of a pulse delay can be linked directly to the presence of the EEA process.
KW  - Exziton
KW  - Spektroskopie
KW  - Exciton
KW  - 2Dimensionale Spektroskopie
KW  - EEA
KW  - exciton-exciton
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-178482
UR  - https://aip.scitation.org/doi/full/10.1063/1.5086151
N1  - This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in J. Süß et al.,J. Chem. Phys. 150, 104304 (2019); https://doi.org/10.1063/1.5086151 and may be found at https://doi.org/10.1063/1.5086151
ER  - 
TY  - JOUR
A1  - Dostál, Jakub
A1  - Fennel, Franziska
A1  - Koch, Federico
A1  - Herbst, Stefanie
A1  - Würthner, Frank
A1  - Brixner, Tobias
T1  - Direct observation of exciton–exciton interactions
JF  - Nature Communications
N2  - Natural light harvesting as well as optoelectronic and photovoltaic devices depend on efficient transport of energy following photoexcitation. Using common spectroscopic methods, however, it is challenging to discriminate one-exciton dynamics from multi-exciton interactions that arise when more than one excitation is present in the system. Here we introduce a coherent two-dimensional spectroscopic method that provides a signal only in case that the presence of one exciton influences the behavior of another one. Exemplarily, we monitor exciton diffusion by annihilation in a perylene bisimide-based J-aggregate. We determine quantitatively the exciton diffusion constant from exciton–exciton-interaction 2D spectra and reconstruct the annihilation-free dynamics for large pump powers. The latter enables for ultrafast spectroscopy at much higher intensities than conventionally possible and thus improves signal-to-noise ratios for multichromophore systems; the former recovers spatio–temporal dynamics for a broad range of phenomena in which exciton interactions are present.
KW  - energy transfer
KW  - self-assembly
KW  - optical spectroscopy
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-226271
VL  - 9
ER  -