Significant Improvement of Photo-Stimulated Luminescence of Ba4(Si3O8)2:Eu2+by Co-Doping with Tm3+

High-brightness green photo-stimulated luminescence (PSL) is observed in Ba 4 (Si 3 O 8 ) 2 :Eu 2+ phosphor when thulium is co-doped upon the infrared stimulation at 808 nm after pre-irradiation with ultraviolet (UV) light. Both the photoluminescence (PL) and PSL spectra of Ba 4 (Si 3 O 8 ) 2 :Eu 2+ , Tm 3+ reveal that only one asymmetric broad emission band located at 496 nm is observed, which is ascribed to the 5d-4f transitions of Eu 2+ ions in two different sites. The optimized PSL of Ba 4 (Si 3 O 8 ) 2 :Eu 2+ is obtained with co-doping with Tm 3+ as the concentration of which reaches 0.02 mol, whose intensity is increased by a factor about 12 in comparison with that of Tm 3+ free samples. It could be ascribed to the new deep traps (T B and T C ) formed for the incorporation of Tm 3+ .