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铈掺杂的焦硅酸镥晶体(简写为LPS:Ce)是新近发现的一种具有潜在应用价值的无机闪烁晶体。本文用提拉法成功地生长出尺寸为15mm×40mm的LPS:Ce晶体。XRD结构测试表明,该晶体属于单斜晶系,C2/m空间群,晶体中分布有少量的LPS和石英颗粒包裹体。对从毛坯中切割出的无色透明晶体样品在室温下分别进行了透射光谱、紫外激发、X射线激发发射光谱和衰减时间测试。结果表明,铈(Ce3+)离子掺杂使LPS晶体的紫外吸收边从175nm红移到350nm,紫外和X射线激发的荧光光谱中都可以分解出384nm和412nm两个发射峰,它们分别对应于电子从铈(Ce3+)离子的5d轨道向4f轨道的两个能级(2F5/2和2F7/2)的辐射跃迁,从衰减曲线中可以拟合出一个38.75ns的时间常数。这些发光特征与该晶体独特的晶体结构密切相关。
Cerium doped pyrosilicate 镥 crystal (abbreviated as LPS: Ce) is a recently discovered inorganic scintillation crystal with potential applications. In this paper, the Czochralski method successfully grown LPS: Ce crystal with a size of 15mm × 40mm. XRD results show that the crystal belongs to the monoclinic space group C2 / m with a small amount of LPS and quartz inclusions. Transmission spectra, UV excitation, X-ray emission spectra and decay time tests were performed on colorless and transparent crystal samples cut from the blank at room temperature. The results show that cerium (Ce3 +) doping can red shift the UV absorption edge of LPS crystal from 175nm to 350nm. Both emission peaks of 384nm and 412nm can be decomposed in UV and X-ray excited fluorescence spectra, which correspond to the electron The transition from the 5d orbital of the Ce (Ce3 +) ion to the 2f5 / 2 and 2F7 / 2 of the 4f orbitals can be fitted with a time constant of 38.75 ns from the decay curve. These luminescence features are closely related to the unique crystal structure of the crystal.