Quantum dynamics of exciton recurrence motion in dendritic molecular aggregates

The quantum master equation approach involving weak exciton–phonon coupling has been applied to the investigation of the exciton recurrence motion in molecular aggregate models with dendritic structures. Each monomer in the models is assumed to be a dipole unit (a two-state monomer) coupled with each other by the dipole–dipole interaction. Two types of the dendritic molecular aggregates, which have mutually different interactions through the branching points, are examined. A generation of one-exciton states by an electric field and its subsequent exciton dynamics with and without relaxation terms have been investigated. It is found that the configuration of each dipole unit significantly affects the coherent motions of the exciton population. We also suggest the possibility of controlling the coherent exciton motions by tuning the frequency of an external electric field.