Luminescence et transition non radiative ³T_1u → ³A_1u dans le luminophore BaS:Bi³⁺

Abstract

(b) Emission and excitation spectra of BaS : Bi3+ phosphors are measured a t 300, 80, and 6 K. I n the excitation spectra the A and C excitation bands are observed. I n the emission spectra only one band is observed which is assigned to the transition 3A1U + lAlg on the basis of the measurement of the time-resolved emission spectra and the decay constant of the phosphorescence. The diffused reflection spectra and the magnetic effect on the phonon structure of the emission band are also measured a t 80 and 4.2 K, respectively. The former is compared with the excitation spectra.The reason why the emission band 3T1, -lAlg cannot be observed a t low temperatures is explained by the fact that the probability of the tunnel effect 3T1u -3A1, is larger than that of the luminescent transition 3T1, + lAig.

Luminescence Spectroscopy and Origin of Luminescence Centers in Bi-Doped Materials

“…Luminescence properties of all Bi 3+ -doped alkaline-earth oxides [79,84,85,88,89,91,133,[232][233][234][235][236][237][238][239], sulfides [84,[86][87][88][89][90] and fluorides [92] are similar ( Table 1). The triplet emission of Bi 3+ ions in these materials shows the extremely small Stokes shift and FWHM and the extremely large energy D of the spin-orbit splitting of the triplet RES (up to 265 meV in CaF 2 [92]).…”

“…The only stable Bi isotope 209 Bi has a nuclear spin of I = 9/2. Therefore, in Bi 3+ -doped compounds with a weak vibronic interaction, such as alkali-earth oxides, sulfides, fluorides (see, e.g., [84,86,[88][89][90][91][92] [68] and references therein), where the Stokes shift is extremely small (see Table 1) and even a vibronic structure of the emission and excitation spectra is observed at low temperatures, mainly the hyperfine interaction can be expected to be responsible for the radiative decay of the metastable 3 P 0 -related level. The influence of the hyperfine interaction on the probability of the radiative 3 P 0 → 1 S 0 transitions in Bi 3+ -doped alkali-earth oxides was investigated in [133].…”

Photoluminescent properties of Ba2ZnS3:Mn phosphors

“…Among many semiconductors, wide band gap II-IV compounds such as zinc chalcogenide ZnS [1][2][3] and ZnSe [4][5][6] and alkaline-earth chalcogenide MgS [7][8][9], CaS [10][11][12], SrS [13][14][15] and BaS [16][17][18] doped with activated emission centers are well known to be efficient luminescent materials for the realization of multicolor electroluminescent and cathodoluminescent devices. For emission centers, the transition metal ions and rare-earth ions are found to be suitable.…”

The influence of processing parameters on photoluminescent properties of Ba2ZnS3:Ce phosphors by double-crucible method

“…Rare-earth doped wide band gap II-VI compounds such as the zinc chalcogenide ZnS [1][2][3][4][5] and the alkaline-earth chalcogenides (AES) MgS [6][7][8], CaS [9][10][11], SrS [12][13][14], and BaS [15][16][17] are known to be efficient luminescent materials for the realization of multicolor electroluminescent and cathodoluminescent devices. There is considerable interest in Ce-doped wide band gap phosphor materials for the achievement of full color luminescence because they have the potential to generate blue light with a broad band emission from the 5d-4f transition of Ce 3+ .…”