| Abstract [eng] |
In this thesis we investigate electronic energy transfer and relaxation in molecular aggregates. The main focus of this work is the development and application of the stochastic time-dependent variational approach to open quantum systems. First of all, we derive the equations of motion for an electronic system interacting with vibrational degrees of freedom. Then we analyze the dynamics and regimes of excitonic polaron formation in a model system. The accuracy of the approach is benchmarked, comparing it to a widely used theoretical method. The stochastic time-dependent variational approach is then applied to model the dynamics of optical excitations and the ultrafast time resolved fluorescence spectra in the Light Harvesting Complex 2. Finally, the effect of nonlinear coupling between the molecular system and the vibrational modes on the energy transfer and optical spectra is demonstrated. |
