H. Hosono et al., LONG-LASTING PHOSPHORESCENCE PROPERTIES OF TB3-ACTIVATED REDUCED CALCIUM ALUMINATE GLASSES(), Journal of physics. Condensed matter (Print), 10(42), 1998, pp. 9541-9547
A long lasting green phosphorescence was found in Tb3+-doped calcium a
luminate glasses prepared under a strongly reducing atmosphere. An ele
ctron-trapped centre giving an EPR signal at g = 1.999, an analogue of
the F+ centre in CaO, was induced by illumination with ultraviolet (u
v) radiation and decayed slowly after the illumination was stopped. A
partial oxidation of Tb3+ ions to Tb4+ ions by uv: illumination was ob
served. A mechanism of the long lasting phosphorescence was suggested
to consist of recombination of an electron released thermally from the
F+-like centre with the photo-oxidized Tb3+ (Tb4+).