An isolated deep-trap phosphor for optical data storage

Abstract Next generation optical storage based on photostimulated luminescence (PSL) materials is a significant data storage technology for the information age. For a better signal durability and resolution, it is necessary to develop PSL phosphors with deep traps in a narrow distribution. Accordingly, in this short letter, we report a unique Y 2 GeO 5 :Pr 3+ PSL phosphor with a narrow trap distribution (0.3 eV) and a trap depth of 1.31 eV, which is presently the deepest value. After charging by ultraviolet (254 nm) irradiation (data writing), the PSL of Pr 3+ can be stimulated by an 808 nm (1.53 eV) laser (data reading). This finding reveals that electrons stored in the deep traps are sufficiently stable under a thermal disturbance at room temperature and even under stimulation by a 980 nm (1.26 eV) laser. Additionally, the deep traps are isolated and demonstrate little interference with the shallow traps. Therefore, the deep-trap Y 2 GeO 5 :Pr 3+ phosphor shows potential applications in optical data storage.