Study of energy transfer in KMgF3:Eu–X (X=Gd, Cr, Ce) by the decay model of 6P7/2 exited state of Eu2+

Energy transfer processes between Eu2+ and Gd3+, Cr3+, Ce3+ ions in KMgF3, which are difficult to study spectroscopically, have been investigated by using the proposed four-level decay model of the 6P7/2 excited state of the Eu2+ ion. Gd3+ and Ce3+ transfer its energy to the vibronic transition of the 6P7/2 → 8S7/2 transition of Eu2+, whereas Cr3+ receive energy from Eu2+ via the d–d interaction. The energy transfer from the Eu2+ 4f65d level to the Ce3+ 4f5d state is observed spectroscopically, and the energy transfer mechanism is discussed.