In:
MRS Proceedings, Springer Science and Business Media LLC, Vol. 348 ( 1994)
Abstract:
Detailed properties of the defects and energy transfers responsible for afterglow in transparent sintered ceramic Y 2 O 3 :Eu and (Y,Gd) 2 O 3 :Eu based scintillators have been determined by transient thermoluminescence ('TL) and spectral measurements of afterglow emission. X-ray excited TTL spectra between 150 K and 350 K reveal 4 defect transitions for 3 mole percent Eu. Adequate modeling of this data requires for each defect transition a trap depth energy, an attempt-to-escape frequency, a broadened density of trap state energies, and a trap filling frequency. These defect parameters have been determined and can be used to predict afterglow dependence on time after excitation shut-off, exposure time, and temperature. The afterglow emission spectra at all temperatures are characteristic of Eu under S 6 site-selective UV excitation of these rare-earth C-type structure scintillators. This indicates that states associated with the Eu activator on the S 6 site are the terminal states upon thermal release of trapped charge carriers.
Type of Medium:
Online Resource
ISSN:
0272-9172
,
1946-4274
DOI:
10.1557/PROC-348-503
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
1994
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