A new type of luminescence mechanism in large band-gap insulators: Proposal for fast scintillation materials
A new type of luminescence mechanism in large band-gap insulators: Proposal for fast scintillation materials
复制标题
大带隙绝缘体中的新型发光机制：快速闪烁材料的提议
DOI：
10.1016/0168-9002(90)90267-a
复制
发表时间：
1990
影响因子：
1.4
通讯作者：
S. Sakuragi
中科院分区：
文献类型：
--
作者：
S. Kubota;J. Ruan;M. Itoh;S. Hashimoto;S. Sakuragi
用同步辐射光源研究了BaF_2（180-230 nm）、CsF（220-500 nm）、CsCl（200-300 nm）、CsBr（220-280 nm）和RbF（200-450 nm）的室温发光组分。这些发光成分的激发阈值位于从最外层Ba 2 + 5 p或M+mp（M = Rb和Cs时，m分别为4和5）核心态到导带的能量差处，并归因于X−np卤素价带（X = F、Cl和Br时，n分别为2、3和4）中的电子辐射衰变到最外层核心空穴态。用同步辐射单束团运转测定了上述发光的寿命。测量的寿命（ns）为：BaF 2：0.88±0.02; CsF：2.9±0.1; CsCl：0.88±0.07; CsBr：0.07±0.03;和RbF：1.3±0.1根据上述结果，提出与价带和最外芯态之间的能量差相比具有大带隙能量的绝缘体是快速闪烁材料的候选者，例如CsCl、CsBr、RbF、KF、BaCl 2、BaBr 2和BaI 2。
Luminescence components of BaF2(180–230 nm), CsF (220–500 nm), CsCl (200–300 nm), CsBr (220–280 nm), and RbF (200–450 nm) have been investigated at room temperature by using synchrotron radiation as a light source. These luminescence components have excitation thresholds at the energy differences from the outermost Ba2+5p, or M+mp (m= 4 and 5 for M = Rb and Cs, respectively) core state to the conduction band, and are attributeted to the radiative decay of electrons in the X−np halogen valence bands (n= 2, 3, and 4 for X = F, Cl and Br, respectively) to the outermost-core hole states. Single bunch operation of synchrotron radiation has been used to determine the lifetime of the above luminescence. The measured lifetimes in ns are: BaF2: 0.88±0.02; CsF: 2.9±0.1; CsCl: 0.88±0.07; CsBr: 0.07±0.03; and RbF: 1.3±0.1 From the above results, it is proposed that insulators having large band-gap energy compared to the energy difference between the valence band and the outermost-core state are candidates for fast scintillation materials, for example, CsCl, CsBr, RbF, KF, BaCl2, BaBr2, and BaI2.