Oxygen transport mechanisms in REAlO₃ scintillators

Abstract

The performance of oxide scintillators often suffers from phenomena related to the existence of point defects. Thus, if deleterious defects are removed, it follows that scintillator performance will improve. In the case of REAlO 3 perovskites, the oxygen vacancy has been identified as the predominant electron trap site. Previous empirical efforts to minimize the concentration of this particular defect through aliovalent doping have been successful. Here we discuss the results of atomic scale simulations that provide important detail regarding the mechanism by which the oxygen vacancy concentration is reduced. Specifically, we describe the complex mobility of oxygen vacancies and interstitials, which governs the recombination of these defects. The results of these simulations will aid in the synthesis of optimized scintillation materials.