Exciton effects in coherent multidimensional spectroscopy

This project is related to the following Fields, Subjects and Techniques:

Coherent multidimensional spectroscopies like 3-pulse photon echo and electronic 2D spectroscopy can be used to obtain information about excitonic properties in molecular systems. For example the nondiagonal bands in 2D spectra give direct information about the couplings in the system. Furthermore, timeresolved 2D spectra contain oscillating components with frequencies related to the same couplings. Calculations with model systems have shown that also the three pulse photon echo peak-shift (3PEPS) has oscillating component which is directly related to the excitonic coupling and the unharmonisity of the multiexciton-band energy.

Three pulse photon echo signal for different excitonic systems

Electronic 2D signals of an excitonic dimer. Corresponding Feynman diagrams are shown