Abstract In this work, we made five samples of SrAl2O4: Eu2+, Dy3+, the $\alpha$ phase and $\beta$ phase SrAl2O4:Eu2+,Dy3+ powder and pellet samples, and $\alpha$ phase single crystal. We have measured the emission spectra of all the samples. All the emission peaks are around 520 nm, which correspond to the transition from 4f65d1(2Eg) to 4f7(8S7/2) of Eu2+ in SrAl2O4 host. The intensity of emission of the $\beta$ phase is stronger than that of the $\alpha$ phase. We believe that it is because the Eu2+ ions have occupied the two types of sites in the $\alpha$ phase SrAl2O4 host and the lifetime of the transition of Eu2+ in the A site is longer than that in the B site. This result also proves that the $\beta$ phase of the material is brighter than the $\alpha$ phase. In addition, the $\beta$ phase can be achieved by quenching technique.
Received: 15 July 1999
Accepted manuscript online:
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