论文部分内容阅读
根据钨酸铅晶体 (PbWO4,简称PWO)的缺陷化学和晶体结构特点 ,用光吸收谱、广延X射线吸收精细结构 (EX AFS)和精密X射线衍射 (XRD)方法对高温退火后PWO晶体进行微结构研究 ,获得了其退火前后缺陷变化的情况 ,据此提出生成态 (as grown)晶体中 35 0nm本征色心吸收带起源于V-F 空穴心 ,并指出PWO中紫外区色心吸收带的强度取决于晶体中铅空位和氧空位浓度之差 :[VPb]- [VO];然后 ,结合晶体在紫外光 (UV)辐照过程中色心的转化规律和偏振吸收谱的实验结果 ,提高 42 0nm辐照诱导色心吸收带起源于V0F 双空穴心 .并对所提出的PWO晶体色心模型的合理性进行了讨论 .
According to the defect chemistry and crystal structure characteristics of PbWO4 (PWO), the optical absorption spectra, the extended structure of X-ray absorption fine structure (EX AFS) and the precision X-ray diffraction (XRD) The microstructure of the as-grown samples was studied and the variations of the defects before and after annealing were obtained. It is proposed that the 35 0nm intrinsic color center absorption band in the as grown crystal originates from the VF hole center and the color center absorption in the UV region of PWO The intensity of the band depends on the difference between the concentration of lead vacancies and oxygen vacancies in the crystal: [VPb] - [VO]; then, the experimental results of the transformation of the color centers and the polarization absorption spectra during the UV irradiation , And the increase of 42 0 nm irradiation induces the origin of the color center absorption band in the V0F double hollow cavity. The reasonableness of the PWO crystal color center model proposed is also discussed.