Multiple thermoluminescence glow peaks and afterglow suppression in CsI:Tl co-doped with Eu2+ or Yb2+

12th Europhysical Conference on Defects in Insulating Materials

材料科学;物理学

Bartram, R.H.^1 ; Kappers, L.A.^1 ; Hamilton, D.S.^1 ; Brecher, C.^2 ; Ovechkina, E.E.^3 ; Miller, S.R.^3 ; Nagarkar, V.V.^3

Department of Physics, University of Connecticut, Storrs

CT

06269, United States^1

Alem Associates, 44 Hunt St., Watertown

MA

02472, United States^2

Radiation Monitoring Devices, 44 Hunt St., Watertown

MA

02472, United States^3

关键词: Adverse effect;    Afterglow suppression;    Charge-compensating cations;    Divalent lanthanides;    Electrostatic calculations;    Glow peaks;    Ionic radius;    Scintillator materials;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/80/1/012003/pdf
DOI  :  10.1088/1757-899X/80/1/012003

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

CsI:Tl is a widely utilized scintillator material with many desirable properties but its applicability is limited by persistent afterglow. However, effective afterglow suppression has been achieved by co-doping with divalent lanthanides. The present report is concerned with observation of multiple thermoluminescence glow peaks in CsI:Tl,Eu and CsI:Tl,Yb, attributed to varying distributions of charge-compensating cation vacancies relative to divalent lanthanide co-dopants, and the subsequent modification of these distributions by repeated observations. It is observed that Yb2+provides a slightly shallower electron trap than Eu2+, and that it can occupy a face-centered position by virtue of its relatively small ionic radius; the latter observation is confirmed by electrostatic calculations. It is also found that repeated observation of thermoluminescence in these materials has a modest adverse effect on afterglow suppression.