Effect of Si(4+) co-doping on luminescence and scintillation properties of Lu(3)Al(5)O(12) :Ce,Ca epitaxial garnet films
Abstract
The single crystalline Lu(3)Al(5)O(12): Ce(3+) 0.6%,Ca(2+) 0.6% garnet films co-doped with Si(4+) ions were prepared by liquid phase epitaxy technique and their optical, luminescence, and scintillation properties were studied. The Ca co-doping into theLu(3)Al(5)O(12):Ce films resulted in a drastic acceleration of decay kinetics and decreased light yield due to the oxidization of Ce(3+) into Ce(4+) ions.
The Si(4+) co-doping regenerated the Ce(3+) ions by virtue of charge compensation between Ca(2+) and Si(4+ )ions. The Ce valence changes were evidenced from the optical, photoluminescence and scintillation studies.
Significant differences between the photoluminescence and scintillation properties were observed in Si + Ca co-doped samples. The influence of Si co-doping and the effect of Ce(3+) -to-Ce(4+) ratio on the scintillation properties of Lu(3)Al(5)O(12):Ce epitaxial garnet films is discussed.