Luminescence of Pr3+ ions in sodium B-Al2O3 crystals

An optical spectroscopy study of differently Pr+-doped sodium ?-Al2O3 crystals has been carried out to probe the optical properties of Pr3+ ions in this host material. Therefore the 3P0 -> 3H4 luminescence has been investigated in more detail by recording low-temperature absorption, excitation and fluorescence decay time spectra. Site-selective spectra of the same transition indicate the presence of, at least, two sets of centres for Pr3+ in the conduction planes of ?-Al2O3