Deep-trap persistent materials for future rewriteable optical information storage

Deep-trap persistent luminescent (PersL) materials with enriched traps, which allow signals to quickly write-in and read-out with low-energy consumption, are one of the most promising materials for information storage. In this review, considering the demand for optical information storage, we provide comprehensive insights into the data storage mechanism of PersL materials. Particularly, we focus on various "trap-state tuning" strategies involving doping to design new deep-trap persistent phosphors with controlled carrier trapping-de-trapping for non-volatile and high-capacity information storage. Subsequently, various recent significant strategies, including wavelength-multiplexing, intensity-multiplexing, mechanical-multiplexing, and three-dimensional and multidimensional trap-multiplexing technologies for improving the information storage capacity of PersL phosphors are highlighted. Finally, the challenges and opportunities regarding optical information storage by PersL materials are discussed. We hope that this review will provide new insights for the future development of PersL materials in the field of optical data storage.