Mo^6＋，Gd^3＋，PbF2组合掺杂对钨酸铅发光的改善和光谱分析

Improvement of combined doping among （Mo^6＋, Gd^3＋, PbF2） on luminescence of PbWO4 and spectroscopic analyses

坩埚下降法生长了（Mo^6＋、PbF2），（Mo^6＋、Gd^3＋），（PbF2，Gd^3＋）组合掺杂，及PbF2单掺杂钨酸铅晶体，对样品进行了吸收光谱、光产额、x射线和紫外激发发光光谱等测试和表征，讨论了掺杂对钨酸铅发光的增强效果。掺杂钨酸铅总发光额都得到了增强；在门宽100ns内晶体的光产额都有提高，但在测试门宽在200ns内，（Gd^3＋、PbF2）掺杂样品光产额有所下降。x射线激发发光显示，PbWO4：（Mo^6＋、Gd^3＋）的蓝发光和绿发光分量都有提高；PbWO4：（Mo^6＋、PbF2）蓝发光受到拟制，提高了绿发光成分，晶体光学吸收边明显红移。PbWO4：（Gd^3＋、PbF2）蓝发光得到增强，绿发光得到一定的拟制。光致发光光谱分析表明，Gd^3＋掺杂对PbWO4基质发光有敏化作用。实验证实，F在PbWO4生长中非常不稳定，显示很差的掺杂均匀性。

A series of impurity ions co-doped PbWO4 crystals, mainly PbF2 and （Mo^6＋, PbF2）, （Mo^6＋, Gd^3＋）, （PbF2, Gd^3＋）, have been grown by the Czochralski method. The light yield, X-ray excited luminescence, excitation and emission spectra, optical absorption measurements were conducted to evaluate the doping effects on the luminescence of PbWO4. The experiments show that these doping are preferable to enhance the light yield of PbWO4. In gate time lOOns, all the doped crystals have larger light yield than that of pure PWO; however, in 200ns, PWO： （Gd^3＋, PbF2） has lower light yield. Based on the results of X-ray excited luminescence spectra, PbWO4：（Mo^6＋, Gd^3＋） has enhanced blue and green luminescence components; PbWO4：（Mo^6＋, PbF2） has stronger green luminescence components, and depresses the blue luminescence components with a larger shift of absorption edge to red wavelength; PbWO4：（Gd^3＋, PbF2） enhances blue luminescence components and reduces the green luminescence components. Photoluminescence spectra confirm the contribution of Gd^3＋ to luminescence of PbWO4. The PbF2 doping experiments indicate the intense evaporation of F during the crystal growth.