Thermally stimulated luminescence of bismuth germanate ceramics with the benitoite,eulitine, and sillenite structures

Thermally stimulated luminescence (TSL) of Bi₂Ge₃O₉, Bi₄Ge₃O₁₂, and Bi₁₂GeO₂₀ and the primary components Bi₂O₃ and GeO₂ was studied under x-ray excitation. Thermal activation energies and frequency factors of trapping centers in the studied ceramics were determined. The relationships of TSL bands of the studied ceramics with maxima at 141–145 and 166–170 K and damage to the Ge sublattice and of TSL bands with maxima at 104–110 and 180–190 K and recombination processes in the Bi sublattice were demonstrated. Recombination processes causing luminescence upon nonequilibrium charge carrier release from trapping centers occur in structural complexes of similar configuration that contain the Bi ion in a nearest environment of O atoms. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 3, pp. 359–364, May–June, 2008.