Evidence of Optically Stimulated Luminescence in Lu3Al5O12:Ce

Lutetium aluminum garnet, commonly known as LuAG, is a versatile material finding numerous optical applications, and whose scintillation properties have been widely investigated. In this study, experimental evidences of optically stimulated luminescence (OSL) phenomena occurring in LuAG:Ce crystals are shown. After demonstrating the possibility to optically bleach an electron trap responsible for a thermally stimulated luminescence (TSL) peak at 280 °C (heating rate 1.7 °C s−1) using red light, a direct measurement of the OSL decay curve and of the resulting characteristic Ce3+ 5d-4f emission spectrum is carried out. The assessment of the bleaching spectrum of the TSL peak at 280 °C reveals that light with wavelength in the 600–650 nm interval is the most efficient in depleting the TSL peak, making He-Ne lasers suitable sources of optical stimulation. The finding of OSL features in LuAG:Ce paves the way to new application perspectives. In particular, the achievement of a good balance between scintillation and energy storage properties of LuAG.Ce can drive a constructive integration between X-rays imaging approaches based on photo-stimulable phosphors and those exploiting scintillating materials.