GROWTH AND OPTICAL-PROPERTIES OF IRON, COBALT AND NICKEL DOPED BISMUTH SILICATE CRYSTALS

The conditions for growing bulk crystals of Bi12SiO20 (BSO) doped with Fe, Co and Ni have been studied and the segregation coefficients dete rmined. Transmission and reflection spectra have been measured and abs orption coefficients calculated in the 0.38 - 0.85 mum range. Fe dopan t concentration - dependent change in transmission specra was detected . Fe concentration in excess of 1.8 mol % in the melt was found to ble ach the crystals manifested in spectral pattern blue shift and absorpt ion decrease. Co doping strongly shifts transmission to the red reduci ng the absorption shoulder. Ni dopant was not found to produce marked changes in optical behaviour.