Suppression of Host Luminescence in the Pr:LuAG Scintillator

Author

Ogino, Hiraku ; Kamada, Kei ; Yoshikawa, Akira ; Saito, Fumio ; Pejchal, Jan ; Mares, Jiri A. ; Nikl, Martin ; Vedda, Anna ; Shimoyama, Jun-ichi ; Kishio, Kohji

Author_Institution

Sch. of Eng., Univ. of Tokyo, Tokyo

Volume

55

Issue

3

fYear

2008

fDate

6/1/2008 12:00:00 AM

Firstpage

1197

Lastpage

1200

Abstract

Effect of Ga substitution in the (Lu,Pr)₃Al₅O₁₂ (Pr :LuAG) scintillator was examined at the crystals grown by the micropulling down (mu-PD) method. Host luminescence due to an exciton localized around the Lu-Al antisite defect was suppressed by Ga admixture. Concentration dependence was investigated and suppression was observed even at the lowest Ga concentration of 5 mol%. Faster decay time as well as less intense slower components were obtained upon increasing the amount of Ga. In the thermostimulated luminescence measurement, the glow curve peaks are gradually shifted to lower temperatures with the gallium admixture, and noticeable intensity decrease was observed only for the (Lu,Pr)₃(Ga_0.2Al_0.8)₅O₁₂. The undesired quenching effect of Ga on the Pr³⁺ luminescence seems to be reasonably low up to (Lu,Pr)₃(Ga_0.2Al_0.8)₅O₁₂ sample. It is estimated to introduce nonradiative losses of less than 10% with respect to Ga-free Pr:LuAG. Bulk crystals were also grown by the Czochralski (Cz) method and these effects were confirmed.

Keywords

antisite defects; crystal growth from melt; excitons; lutetium compounds; praseodymium compounds; scintillation; solid scintillation detectors; thermoluminescence; (LuPr)₃(Ga_0.2Al_0.8)₅O₁₂; Czochralski method; antisite defect; crystal growth; exciton; gallium admixture; glow curve; micropulling down method; quenching effect; scintillator; thermostimulated luminescence; Educational technology; Electron traps; Gallium; Kinetic theory; Luminescence; Materials science and technology; Photonic crystals; Physics; Solid scintillation detectors; Temperature; Gamma-ray detectors; garnets; nuclear imaging; praseodymium compounds; radioluminescence;

fLanguage

English

Journal_Title

Nuclear Science, IEEE Transactions on

Publisher

ieee

ISSN

0018-9499

Type

jour

DOI

10.1109/TNS.2008.922820

Filename

4545190