Influence of local structures on the energy transfer efficiencies of quantum-dot films

Energy transfer is an important photophysical process that plays a significant role in determining the performance of many optoelectronic and light-harvesting devices. Combining carrier dynamics measurements with Monte Carlo simulations, we study the influence of local microscopic structures on energy transfer efficiencies in quantum-dot films. We find that in thin films, the formation of local domains leads to reduced energy transfer efficiencies, even though macroscopically the energy transfer rate remains intact. Compared to packing density, the vertical interlayer energy transfer has a small impact on the overall energy transfer efficiencies in our structures. In thick three-dimensional films, energy transfer outpaces biexciton recombination, suggesting the possibility to harvest multiexcitons in quantum-dot films for device applications.