The prepared Ti:MgAl₂O₄ crystal samples were annealed at different temperature for 24 h in an air atmosphere, and then the transmission spectra, emission spectra, excitation spectra and photoluminescence decay curve were recorded. Furthermore, electron spin resonance of annealed samples were measured at 130 K. It is found that the absorption bands disappeared and the fluorescence intensity increased after annealed at 1200 °C. And when the annealing temperature is up to 1400 °C, the intensity of fluorescence emission was reduced significantly. These results are related to the oxidation of Ti³⁺ to Ti⁴⁺ and the increase of the disorder of cations. The shortening of fluorescence lifetime of the annealed samples may be related to the decrease or disappearance of oxygen vacancies.

将制备的Ti：MgAl ₂ O ₄晶体样品在大气中不同温度下退火24 h，然后记录透射光谱，发射光谱，激发光谱和光致发光衰减曲线。此外，在130K下测量退火样品的电子自旋共振。发现在1200℃下退火后，吸收带消失并且荧光强度增加。并且当退火温度达到1400℃时，荧光发射的强度显着降低。这些结果与Ti ³⁺氧化为Ti ^4+有关以及阳离子紊乱的增加。退火样品的荧光寿命缩短可能与氧空位的减少或消失有关。