| Abstract
| - Photoluminescence properties of Pr-doped alkaline-earth titanates Pr0.002(Ca,Sr,Ba)0.997TiO3 areinvestigated by emission, excitation, and diffuse reflectance spectra at room temperature. The intensitiesof red luminescence and absorption due to f−f transition of Pr3+ ions increase in the order of Pr-dopedcubic SrTiO3, tetragonal BaTiO3, and orthorhombic CaTiO3. The small red luminescence for Pr-dopedSrTiO3 is increased by substituting Sr by Ca and Ba even if the substituted samples have the same cubicstructure as SrTiO3 and the lattice parameters are close to that of SrTiO3. The red luminescence intensityis intense for orthorhombic samples of which the excitation spectra show a peak corresponding to valence-to-conduction band edge and a shoulder referred to as B band. The photoluminescence properties arediscussed in relation to the crystal structure.
- Pr-doped (Ca,Sr,Ba)TiO3 shows intense red emission by ultraviolet light excitation. The photoluminescence properties such as intensity and wavelength of the peak in excitation spectrum can be controlled to some extent by the average radius of the alkaline-earth ions.
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