Intrinsic and ${\rm Ce}^{3+}$ -Related Luminescence in Single Crystalline Films and Single Crystals of LuAP and LuAP:Ce Perovskites

Intrinsic and Ce-related luminescence of LuAP:Ce single crystalline films (SCF) in comparison with their bulk single crystal (SC) analogs were analyzed for the first time using the time-resolved luminescence spectroscopy under synchrotron radiation excitation. Difference in luminescent properties of SCF and SC are due to the absence of the Lu-at-Al-site antisite defects (AD) and extremely low concentration of vacancy-type defects (VD) in SCF. SCF contamination by Pb ions from flux is noted, which gives rise to an additional emission band in UV range. In SCF, the absence of emission and trapping centers formed by the mentioned AD and VD can explain their favorable timing characteristics with respect to SC. The role of trace impurities in LuAP-based SCF scintillators is considered as well.