Title :
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
fDate :
6/1/2008 12:00:00 AM
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(Ga0.2Al0.8)5O12. The undesired quenching effect of Ga on the Pr3+ luminescence seems to be reasonably low up to (Lu,Pr)3(Ga0.2Al0.8)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(Ga0.2Al0.8)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;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.2008.922820
