  CdSe nanocrystals and aggregates of an aryleneethynylene derivative are
assembled into a hybrid thin film with dual fluorescence from both
fluorophores. Under continuous excitation, the nanocrystals and the molecules
exhibit anti-correlated fluorescence intensity variations, which become
periodic at low temperature. We attribute this to a structure-dependent
aggregation induced emission of the aryleneethynylene derivative, which impacts
the rate of excitation energy transfer between the molecules and nanocrystals.
Energy transfer also affects the electric transport properties of the hybrid
material under optical excitation. This work highlights that combining
semiconductor nanocrystals with molecular aggregates, which exhibit aggregation
induced emission, can result in unprecedented emerging optical properties.
