Dependence of Ce3+ - related photo- and thermally stimulated luminescence characteristics on Mg2+ content in single crystals and epitaxial films of Gd3(Ga,Al)5O12:Ce,Mg

Abstract

Photoluminescence and thermally stimulated luminescence of Gd3(Ga,Al)5O12:Ce single crystals and epitaxial films co-doped with different concentrations of Mg2+ ions are investigated in the 77–500 K temperature range under excitation in the 4f - 5d1 and 4f - 5d2 absorption bands of Ce3+ ions. Influence of Mg2+ ions on the photoluminescence intensity, spectrum, decay kinetics, temperature dependence of the photoluminescence intensity, and the activation energy of luminescence thermal quenching is observed. Co-doping with Mg2+ is shown to result in a drastic reduction of the afterglow and thermally stimulated luminescence and in a strong shortening of the afterglow decay kinetics. It influences also defects creation spectra and the activation energy of the photostimulated defects creation. The Mg2+ - induced changes in the characteristics of the Gd3(Ga,Al)5O12:Ce, Mg single crystals and epitaxial films are found to be strongly different, and possible reasons of these differences are discussed.