为评估辐照对 Cr:MgAl2O4 晶体光谱特性的影响, 采用辐照剂量为 100 Mrad 的 60Co γ 射线照射抛光后的 Cr: MgAl2O4 晶体样品片, 测量了辐照前后的拉曼光谱、透射光谱和荧光特性, 并对辐照前后光谱变化的原因进行了分析。研究结果表明: 样品的拉曼振动峰值的位置和强度都受到辐照的影响, 但振动峰的数量没有改变; 由于色心的吸收, 辐照后 250～600 nm 波长范围内的透射率均明显降低; 辐照前后样品的荧光发射峰位一致, 但辐照后荧光强度明显降低, 同时辐照后的荧光寿命显著增加。

In order to evaluate the effect of irradiation on the spectral properties of Cr:MgAl2O4 crystal, Raman spectra, transmittance spectra and fluorescence properties of the polished Cr:MgAl2O4 crystal were measured before and after γ irradiation with a dose of 100 Mrad, and the mechanism of the irradiation effect were analyzed. The results show that the position and intensity of Raman vibration peak are both affected by irradiation, but the number of vibration peaks does not change. And due to the absorption of color center, the transmittance in the wavelength range of 250-600 nm decreases obviously after γ irradiation. The fluorescence emission peaks of the samples after irradiation are consistent with those of before irradiation, while the fluorescence emission intensity decreases significantly and the fluorescence lifetime increases significantly after irradiation.