Giant enhancement of a long afterglow and optically stimulated luminescence phosphor BaCaSiO4: Eu2+ via Pr3+ codoping for optical data storage

The need for data storage is growing in modern society, and optical data storage (ODS) is considered one of the most promising storage techniques. However, significant challenges must be overcome, including improving the performance of volatile memory and expanding its storage capacity. In this study, we report a novel ortho-silicate phosphor, BaCaSiO4, doped with Eu2+, which exhibits sustained luminescence and optically stimulated luminescence (OSL). Following the Pr3+ co-doping, the long afterglow and OSL performance of BaCaSiO4: Eu2+ significantly improved owing to the substantial increase in trap density. Owing to numerous trapped and released electrons, the optical storage capacity of the OSL material significantly increased. As a proof-of-concept, ODS flexible media were fabricated using the obtained OSL material, based on which reversible information write-in and read-out were implemented using ultraviolet irradiation and optical/thermal stimulation, respectively. Furthermore, the OSL-based ODS mechanism was revealed through a comprehensive study of electron trapping, storage, and release kinetics.