Dynamic disordering effects in differential absorption spectra of excess energy degradation vs. bath-assisted relaxation

Summary form only given. Pump-probe spectroscopy has proven to be a valuable tool to investigate promising potentials of molecular aggregates for applications as highly nonlinear optical materials. As the nonlinearity in J-aggregates becomes dependent on the coherence length (the number of molecules over which the excitation is delocalized), annihilation and amount of disorder in the aggregated chains affects the optical response greatly under strong excitation conditions. Therefore, it is important to figure out how the processes following high intensities (exciton-exciton annihilation and dynamic disordering of the aggregate e.g.) maps onto the time- and excitation-dependent differential absorption spectra (DAS). We have examined theoretically the dynamic disordering effects on DAS by considering two possible routes of energy degradation processes after the exciton-exciton annihilation event theoretically.