We theoretically investigate the dynamics of free carriers and excitons in a semiconductor quantum well (QW) in the presence of fast Förster energy transfer to an organic overlayer in a hybrid organic-inorganic structure. By means of a semiphenomenological approach, we study the competition between the short-time energy transfer from the inorganic QW to the organic layer and other fast processes. In particular, we focus on the dissociation of excitons into unbound electron-hole pairs, which is very fast at high temperatures. Focusing on the example of a GaAs QW donor, we show that the dissociation process induces a significant slow down of the energy transfer dynamics, although the total number of excitations transferred to the organic layer integrated over time remains unaffected. The overall transfer efficiency is mainly determined by the energy transfer time and by the exciton recombination time. Our findings suggest that devices based on resonant exciton energy transfer in hybrid structures could operate efficiently even at room temperature, when a large fraction of excitons in the inorganic layer is dissociated.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 14 Nov 2011|