PSI - Issue 66

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Martha Dima et al. / Procedia Structural Integrity 66 (2024) 153–160 Author name / Structural Integrity Procedia 00 (2025) 000–000

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Fig. 3. Normalized voltage for the GAGG-49 crystal, versus temperature and exposure time.

The luminescence efficiency (LE) of both Gd ₃ Al ₂ Ga ₃ O ₁₂ :Ce crystals show the typical thermal quenching behavior with a constant decrease with increasing temperature [15,17,35]. LE of the GAGG-45 decreases between 29.16 EU at 23.7 o C to 18.30 EU at 150 o C, whereas the corresponding values for GAGG-50 decreases between 32.33 EU at 29.5 o C to 18.85 EU at 157 o C. GAGG:Ce showed comparable or even better performance compared to the majority of previously examined crystals in our laboratory. For example, data for a previously measured CeBr 3 single crystal are also shown. CeBr 3 values drops from 37.94 EU at 26 o C to 9.73 EU at 155 o C. The signal of CeBr 3 is higher than both GAGG:Ce crystals in the low temperature range 26°C-30°C, however as CeBr 3 ’s temperatures rise, its luminescence signal is clearly lower than both Gd ₃ Al ₂ Ga ₃ O ₁₂ :Ce crystals examined in the current study.