Multi-mode readout via opto-mechano-photothermo-responsive luminescence from electron trapping material for optical information storage application

Optical storage material is one of the promising candidates for next generation of information memory medium owing to large capacity, reusable rewritable, and rapid response performance. However, as the typical optical storage medium, electron trapping materials (ETMs) are limited in applications of information preservation or optical display technology due to their single readout route relying on photostimulated luminescence (PSL). A crucial limitation to the feasibility of multi-mode optical information readout is the inevitable mismatch between trap depth and the energy of external stimuli. In this study, by introducing Bi3+ ions as intermediate levels between deep traps and emitters, we developed a LiTaO3:Tb3+/Bi3+ (LTO) material that can simultaneously response to optical, mechanical, and thermal stimuli efficiently, showing as multiple trap-controlling luminescence. The tantalate material was endowed with opto-mechano-responsive readout capacity when assembled with polymer matrix. Moreover, by utilizing LiCaYb0.5Nd0.5(WO4)3 microcrystals (LCYW) with near-infrared-induced photothermy property, we designed a LTO-LCYW bilayer composite film then achieved non-contact thermo-responsive readout of optical information via photothermo-stimulated luminescence. These findings provide a unique perspective for designing multi-mode responsive luminophors and photonic devices towards widespread applications, especially optical display, optical memory technology, and anticounterfeiting.