Photoinduced anisotropy in an ensemble of CdSe/ZnS quantum rods

Abstract

The photoluminescence anisotropy in initially disordered quantum rod ensemble induced by selective photochemical reaction under continuous irradiation with polarized light is demonstrated. A specific long-time relaxation of the photoinduced anisotropy in darkness, which is attributed to rotational diffusion of nanocrystals, is observed in the minutes time scale after an extended period of irradiation. The observed bi-exponential evolution of the photoluminescence intensity under continuous irradiation suggests the development of two photoinduced processes such as photopassivation of surface defects and photooxidation of the quantum rod surface.