F,Y双掺钨酸铅晶体的发光性能和微观缺陷

通过透射光谱、光产额(LY)和光致发光等发光性能测试，研究了F,Y双掺钨酸铅(PbWO₄ ，简称PWO)晶体的发光性能，并利用热释光曲线和正电子湮没寿命谱对F,Y双掺PWO晶 体中的缺陷种类和变化进行了分析. 结果表明：与未掺杂晶体相比，双掺样品在350nm附近 的透过率大大提高，吸收边向短波方向移动约30nm，光致发光谱中出现位于350nm的发光峰 ，双掺样品的LY(100ns内)为未掺杂PWO的2.7倍左右.晶体中主要存在的缺陷为(WO_{3)^{-关键词： F Y双掺钨酸铅闪烁晶体 高光产额 热释光 正电子湮没寿命谱}}

The luminescence and defects of F, Y co-doped PbWO4 crystals

The influence of F,Y co-doping on the luminescence properties and defects of PbW O₄ (PWO) have been investigated by correlated measurements of transmi ssion spectra, light yield, photoluminescence spectra, thermoluminescence and po sitron annihilation lifetime. F doping results in a new luminescence band peaked around 350nm, which gives a significant improvement in luminescence properties of PWO. Meanwhile, Y-dopant efficiently reduces trapping state and accelerates t he scintillation decay process. Compared with the undoped PWO samples, the light yield (100ns) of F,Y co-doped PWO　crystal was increased by a factor of 2.7. Th e main defects (WO₃)^- and (WO₄)^3- in PWO crystals for lack of oxygen during growth were investigated. Thermoluminesc ence results show that the defects in PWO crystals increase when annealed in vac uum and these defects can be also suppressed by annealing in air at 600℃.