Luminescence Properties of Eu[sup 2+]-Activated CaAl[sub 2]Si[sub 2]O[sub 8] by Photoluminescence Spectra

We studied the luminescence properties of Eu 2 + in CaAl 2 Si 2 O 8 . In CaAl 2 Si 2 O 8 : Eu 2 + phosphor, two emission bands were observed. Because the two emission bands of CaAl 2 Si 2 O 8 : Eu 2 + phosphor are quite different, it can be presumed that Eu 2 + ions occupy two types of sites, namely, Eu 1 and Eu 2 . The energy transfer between the Eu 2 + ions are elucidated from the critical concentration quenching data based on the electric multipolar interaction of the Eu 1 and Eu 2 sites, respectively. In addition, the dominant multipolar interaction character of the Eu 2 -site emission center was investigated from the relationship between the emission intensity per activator concentration and the activator concentration.