Cs_(2)HfCl_(6)和Cs_(2)HfCl_(6)∶Tl晶体的生长、光学和闪烁性能研究  

Optical and Scintillation Properties of Cs_(2)HfCl_(6) and Cs_(2)HfCl_(6)∶TlSingle Crystals Grown by the Bridgman Method

作　　者：成双良 任国浩[2] 吴云涛 CHENG Shuangliang;REN Guohao;WU Yuntao(School of Materials Science and Engineering,University of Shanghai for Science and Technology,Shanghai 200082,China;Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 201800,China)

机构地区：[1]上海理工大学材料科学与工程学院,上海200082 [2]中国科学院上海硅酸盐研究所,上海201800

出　　处：《人工晶体学报》2021年第5期803-808,共6页Journal of Synthetic Crystals

基　　金：国家自然科学基金(11975303);上海市自然科学基金(20ZR1473900);上海张江国家自主创新示范区专项发展资金重大项目(ZJ2020-ZD-005);上海市科委“科技创新行动计划”高新技术领域项目(20511107400)。

摘　　要：本文使用坩埚下降法制备了∅7 mm的未掺杂Cs_(2)HfCl_(6)与Cs_(2)HfCl_(6)∶0.2%Tl(摩尔分数)单晶,对晶体样品进行了物相、杂质含量、光学和闪烁性能的研究。该晶体属于立方晶系,空间群为Fm3m。在荧光和X射线激发下,未掺杂Cs_(2)HfCl_(6)晶体的发光主峰皆为380 nm,对应于自陷激子发光。Cs_(2)HfCl_(6)∶0.2%Tl晶体在荧光和X射线激发下,发射光谱中除了存在380 nm处的自陷激子发光,也存在505 nm处Tl^(+)的sp-s^(2)跃迁发光。Cs_(2)HfCl_(6)和Cs_(2)HfCl_(6)∶0.2%Tl晶体的光输出分别为37000 photons/MeV和36500 photons/MeV,在662 keV处的能量分辨率皆为3.5%。在137 Cs源激发下,Cs_(2)HfCl_(6)晶体的闪烁衰减时间为0.37μs(4.2%)、4.27μs(78.9%)和12.52μs(16.9%),Cs_(2)HfCl_(6)∶0.2%Tl晶体的闪烁衰减时间为0.33μs(3.5%)、4.09μs(81.9%)和10.42μs(14.5%)。The∅7 mm undoped Cs_(2)HfCl_(6) and Cs_(2)HfCl_(6)∶0.2%Tl(mole fraction)single crystals were grown by the Vertical Bridgman method.The phase,impurities concentrations,luminescence and scintillation properties of crystal samples were studied.Both crystals belong to the cubic crystal structure and the space group of Fm3m.When excited by ultraviolet light and X-ray,both crystals exhibit an emission peak at 380 nm originated from self-trapped excitons emission,and Cs_(2)HfCl_(6)∶0.2%Tl crystal exhibits an extra Tl^(+)sp-s^(2) transition induced emission at 505 nm.Cs_(2)HfCl_(6) and Cs_(2)HfCl_(6)∶0.2%Tl possess high light yields of 37000 photons/MeV and 36500 photons/MeV respectively and both have excellent energy resolutions of 3.5%at 662 keV under excitation of 137 Cs source.The scintillation decay time of undoped Cs_(2)HfCl_(6) is comprised of 0.37μs(4.2%),4.27μs(78.9%)and 12.52μs(16.9%).The scintillation decay time of Cs^(2)HfCl_(6)∶0.2%Tl is comprised of 0.33μs(3.5%),4.09μs(81.9%)and 10.42μs(14.5%).

关 键 词：Cs_(2)HfCl_(6)∶Tl 自陷激子发光 sp-s^(2)跃迁 闪烁晶体 坩埚下降法 能量分辨率 

分 类 号：O734[理学—晶体学]