Studies of electron-vibrational interaction and crystal field splitting in 5d states of Eu2+ in CaAl2O4 co-doped with Eu2+ and Er3+

Abstract

CaAl2O4 co-doped with Eu2+ and Er3+ were prepared by the solid-state reaction method and investigated for their photoluminescence properties. Broad band UV excited luminescence was observed for CaAl2O4 : Eu2+, Er3+ in the blue region due to transitions from the 4f65d1 to the 4f7 configuration of the Eu2+ ion. From the analysis of excitation and emission spectra, the crystal field splitting of the 5d states of Eu2+and the parameters of electron-vibrational interaction, such as the Huang–Rhys factor, effective phonon energy and zero-phonon line position of this system, were estimated for the first time.