Enhancing the optical information storage performance of Ca3Ga4O9: Bi3+ by co-doping with Zn2+ ions

The generation of optical storage based on phosphor materials is a significant new technology for data storage. A key material is Ca3Ga4O9: Bi3+ which has the potential for real-time reading of optical information. This paper describes data from a series of Ca3Ga4O9: Bi3+, Zn2+ phosphors synthesized via a high temperature solid-state reaction. Zn2+ ions had been co-doped as charge compensators to improve the performance of optical information storage. The influence of Zn2+ ions on both structure and luminescence properties are reported. It is clear that co-doping of Zn2+ ions can enhance the emission of Ca3Ga4O9: Bi3+ phosphors via charge compensation and lattice distortions. Photoluminescence peaks of the sample at 528 nm, 500 nm and 484 nm correspond to the transition of Bi3+ due to changes in occupancy of different Ca2+ positions. Thermoluminescence data suggest that Zn2+ ions associate with the defects inside the Ca3Ga4O9: Bi3+ which reduce cation vacancies so as to reduce the number of shallow traps, and increase the concentration of the valuable deeper traps.