Photon conversion in Bi3+/Pr3+-codoped CaTiO3.
Résumé
The luminescence properties of CaTiO3 both singly and doubly doped with Bi3+ and Pr3+ have been measured in different experimental conditions in order to investigate the de-excitation processes active in these materials and in particular to understand the mechanism responsible for the significant increment of the red emission observed in the codoped system upon near-ultraviolet (NUV) excitation. The steady state spectra and the decay profiles have been analyzed in the light of the possible interactions between active ions and host lattice. The general model applied to the analysis of the temporal profiles of the emission allows us to assess which are the main mechanisms involved in the Bi3+ → Pr3+ sensitization process.