Excited states dynamics under high pressure in lanthanide-doped solids

The latest results on high pressure investigations of luminescence related to Pr3+ and Eu2+ in different lattices are briefly reviewed. The influence of pressure on anomalous luminescence and 4fn−15d1→4fn luminescence in BaSrF2:Eu2+ and LiBaF3:Eu2+ systems and Pr3+ 4fn→4fn emission quenching is presented and discussed. A theoretical model describing the impurity-trapped exciton as a system where a hole is localized at the impurity and an electron is captured by Coulomb potential at Rydberg-like states is developed. The results show the importance of local lattice relaxation for the creation of stable impurity-trapped exciton states. The ligands shifts create a potential barrier that controls the effect of mixing between the Rydberg-like electron and localized electron wave functions.