Rewritable Optical Information Storage and Dual‐Channel Encryption Based on Near‐Infrared Enhancement of Photostimulated Luminescence Phosphors

Abstract With the rapid advancement of information technology, the demand for data storage has grown significantly, and optical information storage has attracted considerable attention due to its unique advantages. However, current storage technologies are primarily based on single‐channel and visible light regions, limiting the security of existing optical information storage. Thus, it is necessary to develop new materials and a multi‐channel encryption strategy based on invisible light. In this work, we report a Ruddlesden‐Popper phase Ba 2 SnO 4 phosphor with photostimulated luminescence (PSL) properties, and enhance its near‐infrared emission through fluorine substitution to achieve multi‐level optical information encryption. The enhanced mechanisms are elucidated by investigating the effects of fluorine‐induced lattice distortion and the enrichment of self‐trapped excitons (STEs) due to increased oxygen vacancies. Additionally, density functional theory calculations reveal the influence of F substitution on the formation energy of oxygen vacancies, providing insight into the specific oxygen vacancy sites that contribute to the enrichment of STEs. Furthermore, it is observed that the PSL properties exhibit repeatable capabilities. Based on this, a dual‐channel encryption scheme using visible and invisible light for information encoding is designed, offering a new approach to optical information storage and encryption.