Long‐Lived UV‐Rewritable Luminescent Memory in a Fluoroperovskite Crystal

Photostimulated luminescence phosphors are promising candidates for next‐generation optical data storage devices. Herein, optically‐reversible luminescence modulation is demonstrated using UV wavelengths in the fluoroperovskite RbCdF3:Mn, where the modulation is mediated by photostimulated luminescence processes. UV‐C stimulation enhances the luminescence from Mn2+ centers and simultaneously fills electron traps. This charging process occurs via electron transfer from Mn2+ ions to fluorine vacancies, yielding Mn3+ ions and F‐centers, and is mediated by conduction band transport. UV‐A stimulation restores the material to the initial state. This discharging process occurs via electron transfer from F‐centers to Mn3+ ions and is similarly mediated by conduction band transport. Moreover, the discharging process manifests Mn2+ photostimulated luminescence. The primary trap state has activation energies in the range 1.46 to 1.73 eV and has room temperature lifetimes exceeding 40 000 years. A kinetic model is presented and evaluated that accurately describes the charge transport and luminescence properties of the material. Thus, a material is presented via which ultra‐long term, multi‐level luminescent data storage can be realized, and a model via which precise control over the luminescence modulation and photostimulated luminescence intensities can be achieved. Ultraviolet stimulations can be used to modulate the Mn2+ luminescence in single crystals of RbCdF3:Mn. The modulation is mediated by the transfer of electrons to and from Mn2+ ions and electron traps, and the electron traps have lifetimes exceeding thousands of years. The transfer is understood through a two‐level kinetic model.