Excitonic energy transfer in Au-doped and undoped Kr solids

Abstract

Excitation of Au-doped krypton solids with synchrotron radiation in the range of the krypton excitons leads to the emission of the molecular self-trapped exciton at 8.41 eV and to a characteristic Au-atom fluorescence at 2.74 eV. By measuring simultaneously the fluorescence-yield spectra of these two emissions and their dependence on parameters such as sample thickness and temperature, crystal quality, and Au concentration, information on the excitonic energy transfer is obtained. An exciton diffusion model describes the measured spectra quantitatively. Exciton diffusion lengths, diffusion constants, and the trapping rate at the Au atoms are evaluated from the data.