摘要
Cs_(2)LiLaBr_(6)∶Ce(CLLB∶Ce)晶体n/γ双读出闪烁性能优异,其实用化瓶颈在于大尺寸、高光学质量晶体的生长。本研究采用非化学计量比配比,避开CLLB∶Ce非一致熔融组分区域,通过改进研制坩埚下降法晶体生长炉,并优化温度场和降低坩埚下降速度等晶体生长工艺,从而克服组分过冷,保持生长界面稳定,得到了直径1英寸(1英寸=2.54 cm)的CLLB∶Ce晶体毛坯,等径透明部分长度达40 mm,单晶比例由52%提高至79%,可见光区光学透过率达到70%以上。在^(137)Cs激发下能量分辨率达3.7%,在^(252)Cf激发下晶体的品质因子达到1.42,可以很好地甄别中子和γ射线。
Cs_(2)LiLaBr_(6)∶Ce(CLLB∶Ce)crystal has excellent neutron-gamma dual readout performance,while its application bottleneck is to grow single crystals with large size and high optical quality.In this study,non-stoichiometric ratio was used to avoid the phase region of in-congruent CLLB∶Ce.By improved Bridgman furnace,optimizing the temperature field and reducing the lowering speed,the constitutional supercooling was overcame and the stability of the growth interface was maintained during the crystal growth process.1-inch diameter CLLB∶Ce crystal ingot was obtained,the length of the equal diameter transparent part is 40 mm,the proportion of single crystal increases from 52%to 79%,and the optical transmittance in the visible light region is above 70%.The energy resolution of CLLB∶Ce is about 3.7%under^(137)Cs excitation while the Figure-of-Merit of CLLB∶Ce is about 1.42 under^(252)Cf excitation.This shows good properties for discriminating gamma-ray and neutron.
作者
何君雨
李雯
魏钦华
童宇枫
吴云涛
杨洁男
向鹏
秦来顺
HE Junyu;LI Wen;WEI Qinhua;TONG Yufeng;WU Yuntao;YANG Jienan;XIANG Peng;QIN Laishun(School of Materials and Chemistry, China Jiliang University, Hangzhou 310018, China;Artificial Crystals Research Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201899, China)
出处
《人工晶体学报》
CAS
北大核心
2021年第10期1879-1882,共4页
Journal of Synthetic Crystals
基金
国家自然科学基金(11975220,51972291)
核探测与核电子学国家重点实验室资助项目(SKLPDE-KF-202110)
国防科技工业核材料技术创新中心项目(ICNM-2021-ZH-13)。
关键词
CLLB∶Ce
闪烁晶体
坩埚下降法
组分过冷
光学透过率
中子探测
CLLB∶Ce
scintillation crystal
Bridgman method
constitutional supercooling
optical transmittance
neutron detection
