Stoichiometry and doping induced modifications in the properties of Bi12SiO20 single crystals

Bismuth silicon oxide (Bi 12 SiO 20 ) single crystals were grown from the melts with different SiO 2 mole percentages and with different dopants by Czhochralski technique. The absorption coefficient for these crystals depends on the stoichiometry of the melt composition. Photoluminescence emission spectra for the grown crystals were measured from 80 to 293 K. The spectra present a broad structureless peak at 80 K. The interband transitions for different stoichiometric crystals were analysed and the behavior seems to be independent of composition unlike the bismuth germanate crystals. The three level interband model proposed for the BGO crystals completely explains the interband transitions in BSO crystals also.