Spectral characteristics of optical storage material CaS : Eu, Sm

As a typical optical storage material, CaS : Eu, Sm powders were prepared by wet method in a reduced atmosphere. XRD, emission spectrum, excitation spectrum, photostimulated spectrum, thermal spectrum, and decay curve were measured. The XRD indicates that the lattice of CaS : Eu, Sm was formed at 1 050 degrees C. Spectra analysis results show that UV can excite the sample as an information input source. When excited by ultraviolet lamp and then stimulated by 980 run laser, the same luminescence with peaks at 635 nm. The photostimulated emission decayed rapidly at first and then slowly. The trap level is deep and can make electrons stable in the trap. The optical storage mechanism of CaS : Eu, Sm is discussed.