Improvement in scintillation performance of Ce, Er codoped yttrium aluminum garnet crystals by means of a postgrowth treatment

Abstract

Samples of Ce, Er codoped yttrium aluminum garnet were annealed in ambient air or under oxygen flow and then sputter coated with Al and annealed in Ar. After this treatment Al diffused in the bulk and filled cation vacancy but this process is possible only after oxygen vacancy coupled to the cation vacancy is filled by an oxygen atom. The scintillator performance was improved from 13.2% full width at half maximum at 662keV to 3.4% for a 10×10×6mm size crystal. These findings provide an effective original approach to defect treatment in garnet crystals.